Finally got around to seeing Watchmen yesterday, so thought I'd just post my thoughts on it while they're still fresh in my mind.
All things considered, I found Watchmen to be a bit of a mixed bag; I really liked certain scenes/aspects/characters, but disliked others. For example, I thought Rorschach and The Comedian were brilliant and that all of their scenes were gripping and well-handled, while I found Silk Spectre II and Nite Owl to be pretty dull and monotonous in comparison. The worst moment of the movie for me was the sex scene - awful choice of music, made even worse by the flame thrower as a sexual metaphor. Bad.
While I think Snyder has done a commendable job with this film (in the sense that it must have been really hard to translate the novel onto the screen), I think the end result proves that the novel is more or less unfilmable. The movie is a rather disjointed bunch of narratives that never really sit comfortably alongside each other and lack cohesion.
There are some excellent scenes and ultimately I did enjoy it (despite its cumbersome nature), but I did leave the cinema feeling a little underwhelmed.