I did play the single player demo, it played ok, but I have played other demos and the release product is 100x better.
I really do not see how the game is better than GRAW1. The AI, which is supposed to be new and improved, is at least 1000000(x a googleplex) worse than the 3 stooges in GRAW1. Plus with 16X AA enabled and everything turned to high, and trust me, my pc can more than handle that, the game should look photo realistic. It looks HORRIBLE. What happened to the old Tom Clancy games that ruled, that were capable of soup-to-nuts modding? The original GR series, Rainbow 6 (not Rainbow 6 3, that is Unrealbow 6 IMHO), Again this is my opinion, I am not holding a poorly pixelated M416 to your head and telling you not to play this game, I am simply giving my feedback to this coaster of a game.
The worst part is, after playing the online demo with all the CS fanbois hacking away, I was actually looking forward to the SP campaign. Too bad.