A lot of people say that one benefit of the extended primary has been to force Obama to build organizations in states he might have neglected--or at least to build them earlier than he would have. I've always responded that Obama would have built organizations in key states whether or not he was contesting a primary there--that pretty much anything a contested primary forced him to do he could have done had he already wrapped up the nomination.
However you feel about this question, though, Florida should shed some light on it come November. I'd guess that the Obama organization there turns out to be just as strong as the Obama organization in, say, Ohio, which benefited from the contested primary. But we shall see.