That, and the longer he can drag it out the stupider he makes his enemies look when the other shoe finally drops.
Addendum: I also forgot the obvious political timing issue — making his opponents looks stupid during the height of the 2012 campaign obviously does Obama a lot more good than making them look stupid now.
Yep. I may disagree with his policies but one doesn't get to become President by being an idiot. Obama is allowing this issue to drag on because he feels it is politically expedient to do so. When (or if) it becomes politically expedient to put the issue to rest, he'll do so as well.
Rush has urged conservatives to remain cautious on this. I'll follow his advice.