Why are you in this thread if you haven't watched it period? And tomorrow, I can almost assure you, will be an extremely fun day starting from the first Cat 3 climb. I expect Brice Feillu and Egoi Martinez to be part of a breakaway--except Feillu isn't far out of GC, so I think we'll see the real GC contenders keep him on a short leash and set up attacks from Evans, Menchov, Sastre, and Schleck rather early. Look for Lance, Contador and Kloden to keep them close, but not get really involved until the final climb, where Nocentini will lose the yellow jersey to Contador, and I wouldn't be surprised if Armstrong gets mopped up by the serious climber trio of Sastre, Evans, and Schleck. While he can definitely keep up with the GC guys when they are riding 80-90%, which only about 15 riders can do, I really doubt he will be able to roll with some of the best climbers of the decade (also 5-10 years younger than him) when they are near their breaking point.
I think if Andy gets a bit of a jump and has Frank up supporting him, he is a good pick to leapfrog Armstrong into second of the contenders.