Just saw. Review will probably be up at Escapist tomorrow afternoon. But, very briefly:
This is one nutty movie, and I think it's the most "action" fun I've had at any movie this summer unless you want to count "Up" as action. It's as malnutritious as a giant bowl of Count Chocula, but it's also every bit as fun and nostalgiac. The whole thing plays out like they dumped a bucket of Joe figures on the floor with a couple of little kids, TRANSCRIBED the ensuing afternoon's make-believe session ("And then Snake Eyes was there! And then Storm Shadow came, and they had a fight! And then the two girls had a fight! And one of them could be invisible! And then Storm Shadow had a jet-pack! And then...") and spent $175 Million making a 90-minute movie out of it. I regard this as high praise... I'm not sure everyone else will.
But I think EVERYONE should at least go see it, because I like this as a "template" of how to do these better than "Transformers." Ninja-with-a-jetpack wins every time ;)