Wasn't impressed with first half of movie, little too cheesy. Second half was a blast. PQ and AQ were great, and the bass when Donatello uses his staff to flip the truck...Oh my goodness.
Didn't really like the "let's retire the old guys theme", since that is, after all, what the series of movies is based on - older action film stars in an action film - so it kinda ran counter to the whole idea of the franchise. Other than that, it was a ton of fun. Turn your mind off and enjoy the action, snack on some popcorn and laugh at some of the lines. Really enjoyed the addition of Harrison Ford and Mel Gibson as the bad guy.
I saw the final Hobbit movie in IMAX 3D a few days ago. The movie itself was pretty good with lots of really cool action scenes.
The IMAX 3D presentation was really the best part though. Normally I prefer to watch movies on my own TV and surround setup but there is something special about seeing visually impressive movies like this on that giant IMAX screen.