Unlike Mission Impossible II, and Mission Impossible III, (which are two of the five worst movies ever. [The other three are Batman and Robin, Men in Black II, and Avatar,) Mission Impossible IV: Ghost Protocol, besides being a tad dull, is not a bad film. It doesn't follow the Rule of Fours, (which is that when a trilogy ads a fourth movie, it is the worst thing ever... usually. [See Batman and Robin.])
The beginning scene with Sawyer was the best part.
I liked the cast. Simon Pegg is awesome.