This movie is simply the greatest movie I have ever seen. I liked it a lot more than Lord of the Rings--and Lord of the Rings (ROTK) was my favorite movie until now. This movie has all of the good things. It's very graphic--don't go with someone queasy, as it will spoil the experience. I went to what I thought was an obscure theater that turned out to be magnificent. Soft, reclining chairs are the way to go.
About the movie itself: It has really good acting. It's got a bit of nudity (I don't remember any in the graphic novel.. go figure). And it's got the BEST visuals I have EVER seen. First of all: real visuals. Every single male cast member that was in the 300 men of Sparta is insanely cut. They are literally brimming with muscles. It's the kind of stuff that makes other men go "Holy shit." And then there are the absolutely stunning graphics. The way the blood shoots out of people; the way the spears react with the environment and the flesh of the people they're going through; the way the scenery is. I have never, prior to watching this movie, thought I would have encountered such a beautiful use of graphics. LOTR was good, there's no doubt about it. This blows the shit out of LOTR. The battles of Pelennor and Minas Tirith? Nothing in comparison to even half a scene of action in this movie.
I really strongly recommend anyone with a bloodlust for the one good movie Hollywood will release in the next decade to go see 300 as soon as possible. Try and see it in Imax. I was supposed to go to an Imax theater and watch it but I couldn't because it was sold out and I encountered major traffic. Even in the right regular theater it's still damn fine. The audio is perfect to match the visuals (that were shot in front of blue/green screens for the most part).