John Podhoretz says that the Revenge of the Sith, well, sux. But here’s a much different (and longer) opinion, with lots of spoilers, for those who care about such things.
I have trouble worrying about spoilers for a movie like this. I mean, even someone with the minimal mental acuity of Jar Jar Binks ought to be able to intelligently interpolate between movies 2 and 4, such that the major plot points are obvious. The only question is how well Lucas pulls them all off.