Don't go into this movie expecting it to be exactly like the book (there's a reason that it's "Based" on the book!).
There are things that are altered and changed; there's the battle at Miraz's castle? Where did that come? Susan and Caspian-what? Peter being a total and complete jerk and insulting Caspian? Huh?
There wasn't an obvious set-up for "Dawn Treader", so I'm curious to see how they plan on plotting that out.
Reep is, of course, cute!!
Really, don't go into this expecting Oscar-worthy performances, nor expecting an exact adaptation of the book, because it's neither of those.
It IS, however, a fun ride and a fun movie. Definately darker than the first, but the story itself was a bit dark as well.
Go see it in the theater at least once. Then pick it up on DVD when it comes out.