See this one in 3D if you can...
Just returned from seeing this. The best MI movie hands down. The only niggling downside is that it requires you to have some knowledge of previous movies, particularly the last one, to get a grasp of the complicated double-crosses going on.
That said, as an action movie, the director, Christopher McQuarrie, is one of the few who really knows how to set up sequences that make the most of 3D.
Most directors of 3D movies are usually still stuck thinking in 2D. The 3D is an afterthought that doesn't enhance the movie... one of the reasons, I think, that it hasn't caught on in a big way.
The Paris car/motorcycle chase here is a standout. The director uses unique sliding and low angle shots (a la George Miller) and shallow focus techniques that really put you in the action. The helicopter chase is also fantastic.