I hope everyone will read the impressions I posted, as this is an interesting and very complex game. In fact, there's so much to say that I am thinking about writing even more impressions or a preview update (facts only) before my review.
Also, if anyone has specific questions about the game, you can ask them here and I'll try to answer some of them. And I'll answer the most obvious one right now:
Which is better, True Crime or Grand Theft Auto III/Vice City?
It's hard to answer because they are not as directly comparable as I thought they would be. True Crime is more refined in every way, from graphics to fighting to story. GTA is more open and encourages more exploration. I'm a nut for finding secret packages and bonus missions, so I love all the exploration in GTA. True Crime has some excellent fighting and shooting mechanics that blow away what you can do in GTA, and the storyline is a hundred times better. So it really just depends on what you're looking for and what parts of GTA you like the best.