I really haven't a clue as to what happens after you die. I am a Christian, so I do believe in Heaven, but that is just belief; I don't know there is a Heaven, so I speculate on this a lot.
Assuming Heaven is real, would it look like we all picture - sitting around on clouds, wearing robes, and plucking at harps? Personally, for a place of eternal happiness, that doesn't sound too great to me. And it is that that has led me to my belief: Heaven is different for everyone.
It could be like Terry Pratchett idea that we get the afterlife we believe we will get (Hence why missionaries should be shot on sight; no one goes to Hell if they don't know about it), but what seems more likely is that, since everyone likes different things, we get to shape Heaven for ourselves, doing what we want to do, outside of any rules or punishments (presumably, if you got into Heaven, you wouldn't make it into a hotbed of sins). Who knows? Maybe we all get the chance to be God of our own Universe, if we so choose.