Khaos Komix/WMG

Jamie isn't the Jerkass he appears to be
According to Charlie, he isn't. Previous arcs tend to have shown that the characters are more than they seem; therefore, Jamie probably isn't as much of a homophobic Jerkass as we've been led to believe. Also, his interest in art is shown as a redeeming quality.
 * Sub-theory: Jamie is gay or bi and deep in denial, or insecure. This is not good news for Tab.
 * Judging from the beginning of Alex's Story, this appears to be true, given that he and Alex used to make out when they were 9 and it appears Jamie was anally raped when he was younger
 * What does being anally raped have to do with being gay or bi?
 * I'm going to give the previous troper the benefit of the doubt and assume they just didn't think about how that sentence would sound, but there are people who believe that being anally raped as a boy can make you gay.
 * It could lead to intense shame feelings from the abuse that could lead to internalized homophobia, perhaps?
 * Recent event seem to imply he does care for Alex. Violent moodswings?
 * Well, getting decked by the guy who used to be your bestfriend that you've made out with and then tormented for years could do that to you. Also, there's a good chance that the whole thing with Steve, and his relationship with Charlie made him go through some serious character development, making him less of a douche.

Jamie is saving up for art school
Popular theory on the forums. Jamie comments on saving up for something important.
 * Could be an engagment ring or some other big romantic gift for Charlie.
 * Doesn't fit the timeline.
 * According to a recent comic, he's been working to earn his keep at home -- his mother charges him rent.

Charlie is Tab
They both seem equally defensive about Jamie and people not knowing shit about him. Charlie's artistic enough for a comic, and plots enough things to be a writer, and they're both trans-gendered male to females**. Also, Tab has been hiding her real name from people, going only as Tab Kimpton. In the About section of the site, she says that she has a partner who loves her for who she is.
 * Alternatively, Charlie and Jamie are both Tab, if only because they are both artists capable of drawing a comic.
 * Actually, Tab is female-to-male.
 * Metaphorically? Though I doubt Tab would. This seems pretty jossed now.
 * Couple problems with this whole discussion - Tab is female-to-male, but doesn't really like to think of himself as "male," either. (Although he certainly acts more like Charlie than Tom.) And I'm not sure of this, but "Tab" seems like it's just a less feminine version of "Tabitha."

Someone will be killed in Jamie's Story
I don't know who but I am fairly certain someone will die in Jamie's Story.

Alex' sexuality
So, right, he says he's not gay, and is seemingly just Tom-o-sexual. But what if it's just that he has a trauma from his childhood and is so ashamed of his attraction to guys he's just mentally blocked it. Also, since (re)discovering his sexuality, he is shown to be looking for porn on the internet, and while he apparently imagines himself and Tom in those situations, it does imply he's not entirely blind to the appeal of other guys.
 * He WAS making out with Jaime when he was younger, and one could easily say that the whole thing with Jaime and his parents when they realized what the two were up to was traumatic enough for Alex to not want to categorize himself as gay.

Jamie knows that Charlie is transgendered.
There have been hints that Jamie is actually an Armoured Closet Gay, or at least an Armoured Closet Bisexual: he kissed Alex at least once when they were kids, and Tab has already drawn incentive art of him having sex with Charlie. He could have realized that Charlie was transgendered before he asked her out or sometime shortly thereafter; after all, Amber figured it out just by looking at her. As long as no one knows he knows, he can be with the person he wants to be with and go on pretending to be 100% heterosexual.
 * Sleeping with or being attracted to a trans woman doesn't mean you're gay. Unless you are a woman, at which point, well, it doesn't mean your gay. Just attracted to that one woman. Same for guys.
 * Yes, but most guys Jamie's age wouldn't know that. Besides, there are in-denial homosexual men who like pre-op transwomen because of their genitals, but that is a generalisation.

Jamie is perfectly straight, but homophobic due to being sexually abused as a child

 * Given what we see of his backstory in Alex's story, and what he tells Charlie when she asks what his problem is with Mark and Steve, isn't this pretty much confirmed?
 * The abuse has been confirmed, yes, but I think the "perfectly straight" part has been proven wrong if anything; he's been shown kissing Alex as a child.
 * Sooo...there's no third option, here? Need I remind you of his bisexual GIRLfriend? Sure she's transsexual but that still makes her a girl, right?

Alex is a Grey-A
He fits the label quite well. He's sexually attracted to Tom, and only him. Before him he apparently hadn't felt sexual attraction, though he could have been exaggerating.

Natalie Geln has deep psychological issues of some kind.
What sane person would do that?

There will be a ninth story that serves as an epilogue, revealing that Natalie Geln and Jamie's mother all got some kind of karmic retribution.

 * Well, Charlie's mother did mention Natalie and her friends are probably going to end up in jail soon enough...

Steve and his family are all Time Lords.
Need any more be said?