Excellent point, CO. That's what I've been trying to say since it came out. In a lot of ways, I consider it to be the worst of the prequels. I enjoyed watching its predecessors immensely when they first came out in theatres (even though their values have diminished over time), but ROTS was the only one I actually groaned and laughed at on first viewing. Everyone complains about the turn scene, but compared with some of the other crap in that movie, it was one of the best scenes. The only thing that really interests me is Anakin's story. Despite its flaws, it contains some compelling moments. Everything else was just total crap. Let's review:

The first half hour could have been okay even though it dragged, but R2's craaaazy wild and super cool antics just made me want to vomit. For all of you who hate the Ewoks, R2 in this movie was ten times worse than any Ewok!

Any scene with Grievous automatically made my skin crawl. The whole subplot with Obi-Wan and Grievous was just so torturous and boring. That stupid lizard's howl gave me a headache. Grievous crawling like a bug to his stupid vehicle was just embarrassing. The only thing I liked was the end when Grievous died (because he was finally dead), and Obi-Wan was disgusted at using a blaster. Pointless and annoying minor character.

The Wookie battle. What Wookie battle? I swear, and I know I've said this before, but I left the theatre the first time and about half an hour later I realized there were supposed to be Wookies fighting in this movie... and I had absolutely no memory of it ever happening! When I came back the second time, I prepped myself upon going in to watch out for the Wookie battle. Halfway through it, I realized I hadn't been paying attention to the scene I had told myself to watch out for. To this day, I don't really recall what was going on. It was boring and pointless.

And then a series of scenes that would have been heartwrenching and powerful if not for one, idiotic word: Younglings. I let it slide when Yoda said it in AOTC. I figured it was just some pet name. But, no, this is the official name for Jedi children. When that realization hit me, I was appalled. And then I was amused. And every time the word was mentioned, I would laugh. And I don't think I'm supposed to laugh at a scene where the main characters are agonizing over the slaughter of children. I blame George for turning me into a cold-hearted bastard.

So what are we left with? Anakin's stuff. That's about half an hour to an hour's worth of footage left. Throw back in the Padme and Mon Mothma scenes, and you might have a decent movie.

But what's left contains some really good moments, better than any scenes in the rest of the prequels. But like someone else said, good scenes does not a good movie make. The good stuff is heavily weighed down by the crap, and it's impossible to think of it as a good film. Nothing in the other two prequels managed to match up to the level of crap in Sith.