I see this:
A fast pace over the first climb that sheds the field down to about 60 riders. The entire stage is slightly uphill, which will wear some out. Heading to the Arcalis climb it's moderate grade, so until we get to about 10-15km to go, this group will be the same. As the grade increases, Astana, and maybe other teams, will try to set a "USPS train" hyper fast pace to discourage attacks, but it will only work for so long, and we'll see scattering, then attacks. After that, one of two things:
1 - Contador has to be seething inside with all the focus on Armstrong. People see Berti and see this quiet Spanish guy, and think he's maybe a reed to be pushed over by Lance. Trust me guys (I think you do already!), Contador is a very determined and focused guy. His sole desire on a bike is to go uphill and crush his opponents in the mountains. He has to be burning up inside waiting for the chance to destroy Armstrong, and everyone else, and leave them all in his wake. He may get told by JB to not attack Lance, but someone is going to go up the road, and it might be Schleck, and Contador is going to go with, counter, and completely pour on the gas in the last 5km like he never has before, in an attempt to demolish everyone. Perhaps Schleckette can keep up. Maybe Kreutzier, Moncoutier, Sastre, Evans can stay close. In all logical thinking, Contador should win, and Lance should finish 2+ minutes back, in tow behind Klodi and Levi, around the same time as Rogers, Karpets, Frank, etc.
2 - The grade isn't steep enough, though the climb is long and high. The last time we were here (1997) T-Mob and Ullrich blitzed it, dropping Pantani and Virenque. So, we could see the pace remain fast, and because of the miracle of gear, Lance will be able to stay at the front, and riders will start to burn. Maybe even Contador, maybe. If this happens, anyone posting in the Clinic will know why. I don't think it will happen, but it could.
Menchov will probably drop, and should. He should focus what he can salvage out of his season on the Vuelta...if he makes it that far. Plus, he crashed the other day, so it's a perfect excuse.
Remember, it's highly likely that everyone at the top is on good gear. And with tougher testing, the first situation is likely. But testing, nor good gear, is always equal, so who knows?