This game looks fucking awesome. That said, I am in no way excited or anticipating it at all.
It's weird, every GTA game I've ever played with the exception of Vice City has been nothing but a time-killer and screwing around. IV, I think I played all of 10 or so hours of storyline and missions and furthering the game's progress, and the rest of the 90 hours spent was nothing but dicking around the city, screwing up fools, driving around, etc. etc. I think that with this one as well, all of the little nuances with the pedestrians and the mechanics of the actual gameplay, as well as the secrets they place around the world itself will be what I play this game for.
I never was one to be into the more 'real-world' games such as this, or war games, or anything that makes me realize I'm playing a game and I'm not immersed in a fantasy world; I just don't get into it like I do my precious RPG/Adventure/Other miscellaneous fantasy games. GTA is odd in that you can do whatever the hell you want, but it's all confined to (mostly) real-world physics pushed to their limits and being fantastical in that state of the world. It's awesome but I really couldn't give a shit less about the story, the characters, what happens to them, what they do or where they go; and for that matter, what happens at the end of it all. Truly, I just want to fuck shit up. GTA is perfect for that; so in that regard, I guess I'm somewhat excited. But the real excitement won't come until I actually start doing it.
Good stuff in the world of GTA. It says a lot that the thing that gets me excited is being able to smash my car at the perfect angle across a guard-rail and have my character fly through the windshield, over a pond, and into another car and somehow I still survive...only to climb atop the highest building possible and jump off.