Saw Star Wars III tonight and I rather liked it. It's better overall than Return of the Jedi (no Ewoks) and much better than I or II (no Jar-Jar except for a brief glimpse and a coherent plot). I was annoyed a bit by Anakin's dilemma, which seemed rather solvable, but I think it was meant to be an issue of Control vs Letting Go; could've been made less tractable though.
All in all, I think it belongs in the set with the "classic" three, rather than the two other prequels. Go back and watch them if you don't believe me how much better this one was.