Yes, the movie is very good — a solid piece of entertainment in its own right, and fans of C. S. Lewis will regard it as faithful to his book in every important respect. A few plot elements are dropped and several others are added, but each decision makes sense for a movie that's trying to tell a story in two hours.
Miller goes on to dissect the movie nearly as well as the Monk will when he gets around to seeing it. Be aware that there are some give-aways if you read it and you don't know the story.
UPDATE (from The Monk): Here's a rave review from the San Francisco Chronicle, including very high praise for director Andrew Adamson, who had previously only directed pure CGI films (Shrek, Shrek 2), and for the kids. As I indicate in my review (above), I thought the kids were very good, especially the girls, and far beyond the comparable HP child acting (with possible exception of Emma Watson).