I'm a huge fan of "The Incredibles", the animated Pixar film in which the Fantastic Four type family of superheroes join together to fight crime, and became excited to see M:I 4 when I heard Brad Bird was directing it as well. It was his first theatrical release as a live-action director and I was "incredibly" impressed. There were some beautiful city scapes that took full advantage of the IMAX cameras as well as a plot that moved along nicely. Tom Cruise was great as Ethan Hunt, which he typically is, but I was very impressed with the rest of his team as well.
Jeremy Renner is going to be the next big action star, while "The Hurt Locker" wasn't quite capable of making him an A-List guy, this movie, combined with his turn as a Jason Bourne type badass in the new Bourne movie should establish him as the action star of the 2010s. Simon Pegg is great in his return as the M:I team funny guy and the chick was sufficiently attractive for an action movie.
So far as plot, there are spies, a possible end of the world type scenario that may or may not be averted at the last possible moment, great action sequences, beautiful girls, fast cars, masks, you get the idea.
If you're looking for some fun holiday fare that takes you to beautiful places and keeps you invested the whole time this is definitely the way to go. 8.5/10 (I like throwing an arbitrary 0.5 point in to our new scoring system just because I can)
Also, there's no way this was only 1 point better than "Warrior" so 8.5 was the lowest I could go. Just kidding Dan, I've never seen Warrior, though from reading your review I'd bet it goes for the cheap tug on the heartstrings looking for a reaction a little too much for my tastes.