I’ve sat through Wagner operas that moved the plot forward faster.
Sure, the computer generated imagery is amazing–but overwhelming. It quickly become so ubiquitous that it’s no longer all that impressive (Coruscant looks a bit like Las Vegas at night, oh and look, here comes another floating droid), and without a really strong storyline, the story gets boring fast. The movie didn’t really pick up until 90 minutes in, when Anakin finally turns to the Dark Side. Eventually Yoda busts out some bad-ass Jedi moves, Obi-Wan and Anakin have a lightsaber duel over boiling lava, Padme dies, yadda yadda yadda, and we finally get to see the Darth Vader we know and love. Yes!
General Grievious — a hacking, coughing robot with a shriveled-up hot-dog for a heart? Kinda cool. But thank god there are no more of these movies planned, or we would no doubt be seeing a bad guy wielding eight lightsabers at once.