I love the route, but that's often the case with Vuelta and it can mean nothing. But on paper some climbing stages look evil, so yeah, I also won't be surprised if Cav, Cancellara etc. don't finish. I'm looking forward to night TT in Sevilla as well, should be pretty cool.
About favourites- I agree that Lulu Sanchez looks quite strong lately and he may be among the ones especially hungry for success, as I think he was a bit dissappointed with his TdF performance, not to mention that he's one of the strongest Spaniards (though guys like Anton or Mosquera may be equally dangerous, being fresh and all; and Lulu's teammate Arroyo had a good season so far) and probably has the strongest team. But my types are Nibali and Frank Schleck- both didn't have a chance to prove themselves at TdF though they really wanted to and seem to believe they could do well, and both were in good form this year (I'm not sure if it's still the case though, didn't see Frank for quite a while).
I also think Menchov may surprise again- he said his main target was TdF and he's satisfied, and at Vuelta he'll take it easy and see what happens. But it looks like a perfect situation for him to have a great GT, he's just the type of rider who'll find his chances to come out of nowhere few times and who knows if it won't take him to the very top.
I was also considering Rodriguez as one of the main candidates for podium, but he said he will be more after stage wins than GC. He's probably too tired, which's a shame, because the route seems to suit him.
As for Sastre, I think he may even finish top 10, it's the only GT this year for which he can prepare properly (and I think the fact that it's his 3rd GT this year will affect him less than it normally does, he still raced less this year than for example Menchov).