I think he will win a couple of more but now he has some competition. He just barely beat Andy Schleck who is a few years younger and will get better and better. Luck cost Andy this year because of mechanical problems and Alberto making his attack then which was the difference. Alberto is in his prime but Andy is still young and isn't even in his prime. If Andy can avoid bad luck next year look out. He is on a better team than Alberto even though Alberto's team was better than expected. With his brother Frank back next year Andy may be able to do it. It is a shame that bad luck was a big factor in deciding the race this year.
Of course one also has to consider that he probably missed out on another victory a few years ago through no fault of his own but for the doping of some of his own teammates.
I would guess a couple of more wins for Contador. Besides his own fitness level, it will depend on the development of his rivals (Schleck, at the moment) and on the 'style' of future tours. 2010 was geared for climbers with fewer sprints, only one time trial, and no team time trial.
