*A lot of this has been covered in previews, but thought I'd do a quick summary in case no one wants to read the entire Q&A
You can't play the entire game as one character; sometimes you have to a solo mission as each character to advance the story.
No co-op in the story.
Some missions with all three characters you have to switch between them and then are given the opportunity to choose afterwards.
Can't kill another character when playing as one of the three.
Michael can walk around his house and interact with his family.
Can buy new clothes.
In free roam you choose to play whichever character you want.
Each character is from a different part of Los Santos, but you can go anywhere you want.
Natural Motion Euphoria used just like in IV, RDR and MP3.
Entire map is open from the beginning.
LV and SF definitely not in game.
Downtown area of LS is smaller than Liberty City
During demo, game and switching characters ran perfectly without lag.
Swimming underwater confirmed, plenty of areas to explore.
Plenty of boats and hoes.
Internet on smartphone.
Lots of TV shows.
Trevor able to set things on fire when he wants, not just in missions.
Each character has his own inventory and money. Subject to change before release, though.
No characters from III, VC or SA.
Couple of familiar faces from IV will visit.
Variety of races included; cars, bikes, triathlons.
Still working on Wanted system.
Rockstar didn't answer when asked if Xbox will have multiple discs.
Matt Bertz, the editor at Game Informer that wrote the GTA V article, has just tweeted that the Q&A will be released today.
Hopefully we'll get some fresh insight into the game since the questions are from fans!
Prepping the GTA V reader Q&A, which goes live later today. Damn, you fools sent in a ton of questions!