Just got home from watching it. It was actually better than I expected it to be. The guys playing Murdock and Face pretty much nailed the characters, and Quentin "Rampage" Jackson managed not to completely suck as B.A. The only bit that bothered me was Liam Neeson as Hannibal. He had the mannerisms down, but the voice was just all wrong.
As for the story, there isn't much of one, they do a mission, get betrayed, put in jail, they all break out, and take down the people responsible. Basically, if you saw any of the trailers, you already know the plot. This is pretty much an action movie through and through. There are several scenes that are just plain crazy to watch, and pretty much physically impossible to pull off in the real world, but it's good eye candy. They do manage to toss in some humor along the way to break up all the explosions and such.
As long as you go in expecting it to be nothing more or less a summer action movie, you won't be disappointed.