Ace: That's an interesting theory. After the movie though, I don't think I'd give Lucas that much credit. Coincidence, I think.
Re: Grievous: I haven't seen all of the Clone Wars myself, so I don't know why Grievous has a heart and such, or why he was sick (Mace?) but my dad pointing something out actually, that I missed.
He mentioned that he saw Grievous to be a sort of reverse Anakin, in that he thinks that the heart and the eyes meant that he was at one time an actual person at one time, perhaps messed up, beyond even Anakin's threshold.
Of course, then there's me who just thought that he had a heart so as to be able to have an organic brain, allowing him to think on his own more, maybe give him some connection with the Force. Or just to look neat. Either way, he was way pansy compared to what Clone Wars eps I've seen.