Bit.Trip/WMG

The "BIT.TRIP" is a metaphor for human existence.

 * BIT.TRIP BEAT represents man as an infant.
 * The introduction cutscene with Commander Video coming to life represents conception. (The scene is even called "concept")
 * The three song names, "Transition", "Descent", and "Growth", represent the stages of the egg/fetus during pregnancy.
 * The background images during the songs represent the development of the human body in the womb, with Transition representing the fertilization of the egg (with the shiny comet descending into the large planet), Descent representing the development of the circulatory system (the bloodstreams represented by the lava-filled caves, and the bright red boss chamber representing the heart), and Growth representing the assembly and development of the human brain, and early brain activity. The background images of Growth also resemble the toys a baby would play with.
 * Wait, does this mean the pulsing gray spaceship at the beginning of Transition is... nooo, can't be.(?)
 * The repeating bassline in the second level, DESCENT, may be symbolic of a heart beating.
 * The final cutscene after the credits showing Commander Video moving through a dark tunnel with a light at the end to meet other Commander Videos represents birth.
 * Some other cutscenes seem to show Commander Video trying to learn how to walk, first tripping and then later taking his first steps, which is another infancy-related motif.
 * BIT.TRIP CORE represents man's early childhood and relationship with parents.
 * The song names "Discovery", "Exploration", and "Control" seem related to the steps of learning.
 * The background images during the songs represent the child exploring different environments. In Discovery, the child explores the inside of his own home (with hallways, stairs, and things such as clocks which move). In Exploration, he is accompanied by his parents and ventures outside to explore his neighborhood (viewing streets, other buildings, satellite dishes, and telephone poles). In Control, he departs from his parents and goes to school (the mechanical nature of the backgrounds representing his mind beginning to make sense of things, and also Commander Video-like heads and school desks are visible at some point).
 * The other two Commander Videos in all of the game's cutscenes represent man's parents. The first cutscene depicts the parents (and the third, possibly a babysitter or doctor) as large and frightening entities, much as a very young baby might see them.
 * The second depicts them as guiding figures who hold the child's hand, much to the child's dissatisfaction.
 * The third depicts the child rejecting the parents' guidance and choosing to be independent from them.
 * The final post-credits cutscene depicts the independent child encountering his peers for the first time, and realizing "I AM NOT ALONE."
 * BIT.TRIP VOID represents man's emotional development and relationship with peers.
 * The song names "Id", "Ego", and "Superego" are Freud's well-known terms for the three parts of the human psyche.
 * The first cutscene with Commander Video blowing up his bubble and bumping away the others represents an early child's egocentrism, ignorant of the fact that acting selfish only serves to embarrass him, rather than to impress others.
 * The second cutscene with the other people combining into a large entity and sizing up Commander Video represents the child's realization that he is not intrinsically superior to other people.
 * The third cutscene depicts the child's humility and apology to his peers. He holds hands with them, representing that he has learned how to befriend other people.
 * The fourth cutscene with the people floating away on a circle represents the child taking his place among the new generation of people, all united with friendship or common goals.
 * BIT.TRIP RUNNER represents man's excursion into society.
 * The running represents time; Commander Video must always run at a constant rate and dodge whatever obstacles come, unable to speed up or slow down. Making a mistake is simply a setback, (almost) never a failure.
 * The backgrounds of the game have urban and industrial themes, representing the "working world".
 * The optimism and kinetic energy clearly prevalent in the game's music represents man's eagerness to use his talents to participate in society.
 * The world titles "Impetus", "Tenacity", and "Triumph" refer to man's drive to struggle and become successful among society.
 * The background of Impetus is whimsical and alien, representing a child's wild imagination and dreams (such as a desire to become an astronaut).
 * The background of Tenacity shows more of an industrial environment, perhaps representing man's first job, with the final boss of the area possibly representing man's first encounter with a harsh manager or boss.
 * The third area depicting a city street is much more normal, representing the child letting go of his irrational childish fantasies and his acceptance of the real world. The title of stage 3-1 "Paradise Lost" suggests this as well. Likewise, the melancholy of the music in the final area suggests that this is indeed a depressing reality.
 * The music throughout the game uses the same theme jingle but represented differently in each of the levels. In IMPETUS the music is simple whimsical and happy, in TENACITY it is chaotic and exciting, and in TRIUMPH it is solemn. (The introduction of the single piano helps to drive this home) This correlates well with the theories posted above.
 * The gold which Commander Video collects represents man earning his income. You invariably have to collect some along the way, but collecting all possible gold is an optional task. One might consider it a challenge.
 * Commandgirl Video and the other allies represents man finding love, pets, and a circle of friends.
 * Specifically, Junior Melchkin is someone who looks up to the protagonist, Radbot is someone the protagonist looks up to, Meat Boy is the protagonist's equal (being a fellow video game hero), and Commandgirl Video is, of course, a lover.
 * The final boss, The Source, represents man making enemies with someone or something, finding some wrong which must be righted in the world.

The above theory was jossed by the ending of Runner

 * "YOU... ARE... NOT... A... MAN!" could mean that Commander Video doesn't represent a man at all.
 * This could have been merely The Source attempting to insult Commander Video, though, telling him that he is either a child or a coward.

The sixth game will end with Commander Video dying and/or having a child.

 * If the "Bit.Trip" represents the Circle Of Life, it's only natural that the end of the story would involve the conclusion of one man's trip, or the beginning of another's.
 * Dying in Game 6 is most likely to be Jossed -- signs are pointing to FATE as the game where he dies. Let's hope he's consummated by then.
 * The soundtrack to FATE has been released, and the songs are "Patience", "Frustration", and "Anger"... neither these, nor any of the other songs in the soundtrack, seem to deal with the issue of death.
 * If Commander Video dies in FATE, the sixth game might star his offspring.
 * Confirmed - CV seems to die in FATE.
 * The sixth game is now known: Bit.Trip FLUX. Instead, it may be about the "nether", the ending of his life and the beginning of another.
 * It is.

The Viral Marketing video depicts Commander Video's grave.

 * Word of God says that the campaign will makes sense as time goes on. The video also implies that the Commander was Only Mostly Dead before his body was exhumed.
 * Word of God says you're close.

The difficult-to-get ending is a metaphor for the circle of life.

 * Non-WMG: It has been revealed that a specific action must be taken at the end of the game to trigger the ending, and it has been predicted that few people will figure out what has to be done. WMG: It will involve pressing a button on another Wiimote (or, optionally, a Classic or Gamecube Controller), either triggering the birth of Commander Video's son or causing that son to do something unexpected that continues life's endless cycle.

The difficult-to-get ending is a metaphor for cyclicality itself.

 * At a certain point of the ending, in order to get the full ending, the player must reset or turn off his Wii. Upon starting the game again, the full ending will play.

The difficult-to-get ending is difficult to understand, not to get.
In order to trigger the Game Over of FLUX, the player must let the screen fade to white, then let go of the controller. Continuing to rotate the controller will cause the invisible Commander Video to hit beats and constellations for eternity. In order to complete the BIT.TRIP, one must learn to let go.

The Final Boss of FLUX will be a Perspective Flip of the final boss of BEAT
These two Twitter messages suggest the possibility. Winning against it may even be the way to get a Game Over, as you are supposed to lose to it.

The place to which CommanderVideo goes after the credits of Flux is known.

 * Wait, so are you saying that CommanderVideo is the one who ?
 * Why do you think his symbol is what it is? It appears in binary in the last game, and in the first and last games,
 * Oh, and don't forget - at the beginning, he leaves a blue sphere, and at the end, he returns to it. A single, infinitesimal place in the infinite reaches of the multiverse.
 * Suddenly the dedication makes sense.

The final task of the series is a direct message from CommanderVideo.

 * The final level brings CommanderVideo home.

Both the "What CommanderVideo became" and "The series is CommanderVideo's final message" WMGs are true.
How can the two theories be reconciled? Easy.

The nature of the end of the story has been staring us in the face from the very beginning.
As explained in the manual, the final game is partly about how nothing truly ends, only changes. The entire game is a return to not just the first game, but its first level (as the musical references make clear). Death is only a transition, and guess what the first level of the first game is called?

CommanderVideo is an anthropomorphization of...

 * The paddle from Pong.
 * The letter I.
 * The monolith from 2001: A Space Oddysey (although the proportions are all wrong)
 * Your Wii Remote (there's black Wii Remotes, and the paddle is white in Flux)

CommanderVideo didn't die at the end of FATE.
He died at the end of FLUX.

FLUX is a story of CommanderVideo's final moments as he lays dying. His entire life flashes before his eyes, and he learns to accept who he is and what he has accomplished in life. Once he has gained this acceptance, content and proud of the fact that he has completed his journey, he fades away, having achieved the sole goal of life... whatever it may be.

The entire series is a Dying Dream.
The viral video, depicting the discovery of a mysterious monument (actually the head of a mostly-buried CommanderVideo), is not an epilogue but a prologue. After his suicide attack against the Mingrawn Timbletot, CommanderVideo landed on Earth, where he slumbered for an unknown amount of time until his discovery left him with no excuse to put off his the final phase of his life: its end. The first five games depict what CommanderVideo displays on his visor: a replaying of his life for his own benefit and the benefit of others. The first three parts depict his origins. His memories of those are somewhat fuzzy, and as a result they are largely depicted through metaphor. The beginning of BEAT shows the adult CommanderVideo flying around, before showing his literal conception, as if to say, "Where am I? ...When am I?" The visuals of VOID's gameplay are the most abstract because they depict CommanderVideo's emotional development, which was entirely intangible. After the first five parts are finished, CommanderVideo again becomes conscious of the here and now. A world where he cannot contact his friends remotely and the world is slipping away from him. His thoughts bounce back and forth between simply, imperfectly displayed images of his hallucinations and a glorious visual and aural summation of his life and identity depicting his final journey to absolute clarity. At the very end, his visor displays nothing but pure white. He's waiting for you, with whom he has shared his life's journey. Waiting for you to do what he has done, and say one of the most difficult words in any language: Goodbye.

CommanderVideo's friends all have different, well-defined roles.
Junior Melchikin looks up to him, Radbot is looked up to by him, Meat Boy is his equal, and CommandgirlVideo is his lover.

RUNNER2's different graphical style is how things actually looked throughout CommanderVideo's life.
The original BIT.TRIP series is essentially CommanderVideo hallucinating his life story as he finally begins to die on Earth after his discovery in the viral video. This explains the retro graphical style. RUNNER2, meanwhile, portrays things as they actually looked.

RUNNER2 is told from the point of view of someone who knew CommanderVideo when he was alive.
Judging by the cartoony style, it may be the recounting of idealized memories. The one doing the recounting may have been quite young at the time... downright junior, in fact. Perhaps the player - who previously kneeled before the dying, mostly buried CommanderVideo as his life flashed before (and on) his eye - has met an old friend of the Commander, who is adding to his story. Junior Melchkin, now Senior Melchkin, or perhaps even Commander Melchkin. After all, as a wise man once said, we are all commanders.

FATE was designed to not feel like a rhythm game on purpose.
The notes are still kerned to the rhythm because rhythm is life and vice versa (this only changes when ), but the gameplay is as far from being rhythm-based as the series gets (the second-furthest is VOID). This is because those were the points in CommanderVideo's life when he strayed the furthest from his life's path. In VOID, he was egotistical, and in FATE, he was utterly bitter.