Well the day has finally come where we can all start talking about this game more and more.
The trailer will be "aired" in just over 2 hours on the GTA IV official site aswell as a lot of other freelance sites. I think this is the first time in a long time that I have been even so slightly excited by a game trailer. It's usually GTA that does this to me! I'm a nerd from the time a GTA game is announced up until like 3 months after I get the game.
Many sites warn that you won't be able to access the official site for some time because of all the GTA freaks trying to watch it at the same time. Personally I reccommend either being quick, waiting until everyone has gone to sleep, or waiting until a freelance site gets the trailer up.
I will say this now that I will be uber pissed if I see the setting or something posted on here before I see the trailer!