Cold Case/WMG

The team will be the subject of at least one cold case before the show ends.
So far, while they've been shown to be peripherally involved in the history of past cases, none of the Cold Case team members were ever considered a suspect, major witness, or victim of one; most of the other Jerry Bruckheimer shows (especially CSI) had multiple episodes where its main cast were on the receiving end of an investigation. However, both Det. Valens and Jeffries have old cases tied directly to them (Valens has his and his brother's sexual molestation as kids and his girlfriend's supposed suicide, and Jeffries' wife's hit-and-run murder) that could easily be reinvestigated in a later season, and there's still a lot about Det. Rush's own dysfunctional family history to bring something up.
 * What about the episode where Valens was a witness?
 * Other than him finding the body, he wasn't that involved with the case as a witness. There must be a case where they are heavily involved. In CSI: NY, Bonnasera was tracked down by the Cold Case people because new evidence popped up implicating her as a suspect, and there have been plenty of times on CSI NY where the evidence they themselves are looking at turns out to come from an internal source, or the leads had to step out of a case because one of the suspects is related to them. So far, none of the team members on Cold Case has had that happen to them; there is simply no episode where they or someone they are related to is a suspect in a case they are looking at. Yet.
 * This may have happened in the finale of last season. Or it will happen this season, because the killer in the cold case ending that season committed vehicular assault on Detective Rush before she could make it official, and Word of God suggests that the vehicular assault itself might turn cold!
 * It's likely to happen, but not for the reason you'd think.
 * This happened even earlier. In "Officer Down," Jeffries is one of the victims shot in the prologue, and the squad spends most of the episode investigating him. But the case is 'hotter' than usual because everything but one flashback is set in the previous 3 or 4 weeks.

Watching the Rocky Horror Picture Show with Vera aged Will Jefferies six years.
In episode Creatures of the Night Will is seen to look very bored at the movie screening of Rocky Horror with Vera. So bored, in fact, that it aged him six years. This explains how two episodes before (in Strange Fruit) he is 12 in 1963, but in the episode after (in Best Friends) he is 60 in 2005.

Kat Miller will have something happen to drop her out of the squad sometime soon.
Despite proving herself a competent and determined detective since her introduction in season 3, Kat is still not recognized as part of the Philadelphia homicide team by any of the people coming in to get the team to investigate their cold case. Det. Rush is always called the only female on the force, and the team goes through great pains to correct this. Considering the show's in its fifth season now and this trend is continuing, either the general public (including those supposedly interested in women's positions in power, like in the episode Torn) have mass, laser-guided Genre Blindness towards Kat's promotion, or Kat's days on the force have been numbered from the start.

It's not just a metaphor - the team sees dead people.
Essentially, it's a mild ability that tells them they have the right solution. They can also temporarily give it to others close to the victim to grant some comfort and closure. Why else would they continue to do the job that most of the department considers scut work?

Rose died at the end of Best Friends
Usually, when the above mentioned dead person shows up so their loved one can see them one last time, they smile, loved one smiles, we get an image of what loved one looked like when young, dead person fades away, show over. When Billie appeared to Rose, they actually made physical contact and walked away hand in hand, Rose suddenly a young woman again. They were able to touch because Rose had just died and Billie came to escort her to Eternity.

George Marks was conceived by rape
As they say in "The Woods", Hysterical Blindness is the product of severe trauma in the past. George's mother hates him for no real reason and has blamed him for her blindness since birth, and while she is the epitome of horrible mother the child George keeps returning to her old family home because he has no family but her. Then when she is about to be raped at the end of the episode, that makes her recover her sight. Quite suspicious that this trauma erased precisely the very same effect of that other unknown trauma, don't you think? Maybe the attempted rape sparked memories of a first rape that hit her so hard that "a nail went through another" and undid the effect of the first rape, which had also been the way George was conceived. If this is true, it would make the later bastard George a literal bastard.

Working on from "the team sees dead people" above...
They actually bring closure to the victim's restless spirit, whose ghostly energy manifests as hallucinations showing flashbacks related to the crimes and confessions.

Cold Case and James Cameron's Titanic take place in the same continuity
Specifically, the 5th season episode Slipping was a sequel to Titanic.

Rose got pregnant with Jack after all, conceiving a daughter, and gave her for adoption in Philadelphia (de deWitt-Bukaters' hometown according to Titanic's script) because she had no money to raise her at the time. Eventually she moved to the Midwest where she married her husband, Calbert. Meanwhile, this unidentified daughter (born Dec. 1912) grew up in an orphanage, married in the early 1930s and (as we are told in the episode) went mad after giving birth to another daughter, Nancy Patterson, who was killed in 1962. Eventually, Nancy's daughter Rachel grew up to look just like her great-great-grandmother Ruth.