I read the graphic novel in the fall for the first time and I thought it was pretty damn good. I liked the thoroughness of the novel, even if I didn't think all of the asides and endnotes, or frontnotes, were necessary to the plot. I enjoyed the heck out of it and figured that a significant portion would be cut to make the movie. I don't really have a problem with cutting things for movie adaptations, so long as the directers or producers don't cut characters or plot points that I think are essential. There is basically no way to make an adaptation without cuts, unless you're the BBC and are shooting for a four hour miniseries, so these should be expected. After reading the novel, I had a short think about the cuts I would make, were I making the movie, and I am surprised to say that I was almost right. However, I was not surprised nor was I disappointed by what was cut.
I heard some guy complaining about it as we all filed out, and he compared it to the Harry Potter movies in the list of shitty adaptations. This was a tremendous overreaction. The Potter movies have cut scenes and extended others in a display of poor judgment and changed crucial dialogue. This guy seemed to want a literal transfer of written word and panel to the screen, and I don't expect or want that. If I wanted to see a movie like that, I would just read the book again. The director has a creative vision, usually, and you are watching their team's interpretation of the book or graphic novel. If you accept that, you might find yourself enjoying Watchmen as well.
As a movie, it is extremely entertaining but surprisingly slow at times. The characters were excellent, especially Rohrschach, though Silk Spectre II was perhaps the least excellent. Rohrschach had to be brilliant or the entire movie would have fallen apart. I don't want to spoil anything else, except to say that I thought the changes were fine (unlike the end of The Two Towers) and the movie was great overall. This feels like a pretty limp review but I don't want to give away anything for those who haven't seen it (unlike teh l4m3 and his Battlestar Galactica spoilage). Worth the bullshit of the modern movie theater experience.
I should say that I found the sex scene to be a little ridiculous. The entire theater was laughing at it and that is kinda the point but it lasted long enough to be almost uncomfortable.