My bet: Obama and Clinton "leak" that he offered her the VP slot

[ruggerson]

and that she turned him down, wanting to return to the Senate and help him in the fall.

When the rumor surfaces, both camps, of course, vehemently deny that any such offer ever took place.

If they do this right, she then gets up at the convention, during prime time, and gives the nominating speech for the actual Veep candidate (Clark, Webb, whomever).

This allows Obama to gallantly reach out to her constituency, it allows Clinton to be gracious and get out of a job she really does not want to do, and it allows her to send a clear message to her supporters that she fully supports the ticket.

It could be a PR masterpiece, but it has to be handled with great finesse.