Ewan MacGregor. He's quite believable as a younger Sir Alec, and he's arguably the only actor in these films who can deliver Lucas' dialogue and make it sound convincing. His "You were my brother, Anakin! I loved you!"-speech also managed to be more moving than any of the scenes Hayden and Natalie share.
Ian McDiarmid. With reservations, because while he's a great actor, he turns into a cackling idiot in ROTS. When he's good, he's very good, though, and delightfully slimy. Like when he urges Anakin to kill Dooku. Still a far cry from his performance in ROTJ, though.
Darth Maul, if only appearance-wise. He still looks like a badass. Oh, how it seemed the Prequel Trilogy would get a memorable villain, its Darth Vader, so to speak. Until he got slashed in two after five minutes of fighting. Then we got an underused Christopher Lee and a robot with a funny accent and bronchitis instead. Shucks.
Jango Fett's costume. I love the colour scheme. I would've liked to have seen more of this character, though. Should've kept his face secret, though.
"Duel of the Fates", "Battle of the Heroes" and "Padme's Ruminations." Overall, John Williams' scores are not among his best work, and they're not certainly not up to the standards as the ones of the OT. Those three cues are excellent, however. Among the better pieces of the saga. The latter, especially, really caught me off-guard. The scene was also surprisingly good - why didn't we get more of that in the PT?
The "Order 66"-scene. This was the one scene where George showed he still had some skills as a director and editor. This scene has literally brought me to tears at times, and it's obviously not because I sympathise with our wooden couple Anakin and Padmé. It's a great down-to-business scene which is shot and edited wonderfully (it reminds me of Lucas' montage from "The Godfather"), and Williams' delivers a very haunting theme. Again, another scene that really worked. Hey, notice how both of these were wordless?