Kinberg or Penn stated recently that though they weren't entirely sure, as an exact time frame was never given, around 8 or 9 months seemed like a sensible amount of time to have passed between X2 and X3. I can't remember the exact quote, but no doubt someone will post hit here at some point. My question is, what has happened in that period in between the end of X2 and the start of X3? We know a couple of things. The President: Xavier's talk with the President at the end of X2 had a positive effect. The President changed his stance and instead sought a similar goal to Xavier, integrating mutants and humans in society. He set up the Department of Mutant Affairs (DMA) of which I presume Beast is a government official. At some point, the President was replaced by his successor, who's mutant policy we're yet to discover. He appears to have kept the DMA. The Danger Room: This could well explain how many of the powers have advanced for X3. The characters have each had over half a year to hone their abilities in the Danger Room. The Funeral: We can presume that Jean's funeral would have occured within a month of her death, thus won't be shown in X3. Thus, the funeral is for another character, or for Jean's second death, should she die again.