Pretty soon, as we sink into depression
We can all take heart from knowing that studies show that until the majority of the population falls below poverty level they will not act on their dissension from government policy. After the fall they they will be more amenable to marches on DC, phone and email campaigns, letters to the editor, and so on.
I'd imagine that Obama's supporters are beginning to feel a tingle of doubt about now. Once they realize they've been had, and the hope bubble pops, watch out for some serious blowback. They're young, they're activists, and they're not used to disappointment yet. They may want to involve themselves in the above types of campaigns. They may start thinking of writing manuals on how to make nifty defense weapons from spare parts. They may take advantage of the network they've already formed to coordinate activities.
Somebody better be ready with a plan for success. We don't want to end up with a Bush or Saddam in charge.