Caught this with the wife yesterday. Incredibly fun movie, and worth watching on IMAX. Vin Diesel seemed to be channelling his inner Stallone for a good part of it (slurring words, massive fistfights) and it offered closure to a number of characters from 2 Fast 2 Furious and Tokyo Drift, but still left the door wide open for a sequel.
This is AWESOME!! I can't believe all of the shows I loved as a kid are coming out on DVD... even the crappy ones. Sledgehammer!, Miami Vice, A-Team, 21 Jump Street, G.I. Joe. I agree with Zereul, though.