I am really surprised that TW3 has won so many awards, while TW2 won very little. Did no one play TW2? TW3 deserves acclaim, but it seems that TW2 got glossed over by many reviewers.
It was not marketed as much as TW3, and was initially PC exclusive (later ported to X360), that may explain the relative lack of reviews from mainstream media.
Replaying it recently, it's really brutal, and has so many twists leave your mouth sticking to the floor. I think a post by Scryar sums it up for me.
One the complaints that the devs think people had with TW2, was that it was "too complicated".
It may seem so on a first playthrough, but after playing more than once and trying different paths, one can understand it fully and see how well the story is written. However, I guess the majority of players and reviewers did not actually do that. And even the gameplay is sometimes not very friendly to new players, there are parts of the game that can be frustrating at first (e.g. the kayran), but are much less of a problem on a replay. In the case of TW3, more effort was put into making the game more "accessible" to first time players.