Oh yeah, and Keanu Reeves as Dr. Manhattan.
If you've never read Watchmen, the image on the right is what Dr. Manhattan looks like. So if you can imagine Keanu Reeves as a bald, blue, naked, God-like being...
...which I can't...
On the other hand, I think Reeves did an outstanding job handling the material of the Matrix movies, and Watchmen is on that same level of "thinking man's" entertainment that those films were. Reeves as Dr. Manhattan might make a lot more people stand up and take notice at this project... if it can manage to stay faithful to the book (which is gonna be hard, but after seeing 300 I think that if anyone can pull the impossible off with Watchmen, it'll be Zack Snyder).
And now that I think of it, Reeves seems like an excellent choice to play Jon Osterman, before he becomes Manhattan (read the book if you want to know what happens that turns him nigh-omnipotent). But this is still gonna have to be handled delicately: we should not have people pointing at the screen and laughing at bald blue naked Keanu Reeves, right?
Now, anyone wanna take a stab at who is gonna play Rorschach?