Not that I doubted Snyder himself, per se. 300 is still the best movie that I've seen all year and after how he adapted that to film, I was convinced that he could "probably" do a good job helming Watchmen too. The problem is with Watchmen itself: it's such a dense book, that there's no way to do all that story in 2 or 3 hours.
But now my hopes are soaring for the Watchmen movie: Warner Bros. is letting Zack Snyder shoot Tales of the Black Freighter, to include it on the DVD of Watchmen!
So if you've never read Watchmen, here's the skinny: inside the alternate-1985 universe of Watchmen, superhero comics were only big in the Thirties and Forties, before the real-life superheroes started turning up (well in Watchmen anyway). In place of the superhero comics, pirate comics became all the rage. One part of Watchmen's story involves a young man who hangs out at a newsstand, who is reading a pirate comic book called Tales of the Black Freighter. So we see the story in Tales of the Black Freighter interspersed throughout much of the rest of Watchmen, like this...
It's an extremely violent, gory story. And it would have been insanely difficult to put it in the context of the rest of a Watchmen motion picture. But by putting it as a feature on the DVD... that really is the way to go with this. In doing this, Zack Snyder is showing everyone that without a doubt, he "gets" Watchmen.
Can't wait to see this movie! Heck, I can't wait to buy this DVD! :-)