I thought it was pretty good. I left somewhat disappointed though, I guess I was hoping for more Mace Windu kicking ass or something. I was somewhat letdown by his battle... Was the Emp letting Mace win for awhile there to egg on Anakin, felt like it a bit to me but no-one I went with really thought so??
Kinda disappointed with the battle with Grievous too. I found it strange that for the movie they made no mention of how Mace Windu damn near killed him in the Clone Wars Cartoons, they just left him limping around coughing without explaining it. They should have included that scene in the movie, take all of 30 seconds and would have helped the movie some IMO> His battle with Obi-Wan wasn't quite what I was hoping for...
I also didn't really like the way Anakin lost the battle, felt lame or something. The Emperor's voice annoyed me at times too, they went a little overboard with his "evil voice".
But overall I liked it, lots of good action. But I also liked the previous two movies too so...