Maybe I'm missing something here but going from recent results:
Spanish National TT Championships – Contador wins time trial
Prologue – Contador beats Armstrong
Stage 3 – Armstrong gets 40 odd seconds on Contador due to being in the right place at the right time.
Stage 4 – TTT – Astana have the strongest team and put time into everyone else
Stage 7 – Contador leaves everyone standing – check the video – no-one was getting close to him – Armstrong had to sprint just to cover the attempted chase – there was no way he'd have caught Alberto.
I haven't seen anything that suggest that Armstrong still has it. Sure he's a great rider, and can keep up with the top few in the mountains if he has protection, but there is a big difference between being able to keep up, and having the strength to be able to attack and get away. That's what Armstrong used to be able to do with ease – doesn't look like he can any more. Armstrong hasn't shown anything so far – in fact the only GC contender who has is Contador.
If the roles were reversed, and Armstrong had beaten Contador in the ITT, and left him standing on stage 7, we'd all be on about how he was dominating the tour once again. The fact is he hasn't thus far, and in my opinion can't any more.