VP [UPDATED]
I suppose, Obama has to announce his choice next week, since the Convention begins the week after that. Jerome at MYDD believes the speaking schedule announced rules out some high-profile candidates:

The headline prime-time speaker on Wednesday will be Barack Obama's Vice Presidential Nominee.
...
Former President Bill Clinton will speak on Barack Obama's commitment to a stronger and safer America, as well as the history of Democrats making positive change in the lives of all Americans.

Governor Bill Richardson and Senators Evan Bayh, Joe Biden and Jay Rockefeller will echo Obama's call for a new direction in national security and outline his policies and plans to secure America's future.

That, he concludes, takes Bayh, Biden and Richardson out of the running. But I'm not so sure. What would be so difficult about moving them from one slot on Wednesday to another? Anyway, announcing that slot now gives them a speaking assignment to start working on that speech...presumably before knowing it will really be an address given as the Vice President selection. It's hard to see how this schedule release really rules anyone out.

Or maybe I just want to think Bayh is still in the running. I've warmed up to the idea of his selection for one simple reason: he would bring Indiana. Which other choice has a definite electoral college advantage (besides VA's Kaine)?

[UPDATE: Here's a list of possibles and their supposed status. Those not yet crossed out include also Chet Edwards (who I like a lot, and if Obama's not going with one of the 2 that could win a state, I would be pulling for Chet), Chris Dodd, John Kerry, Wes Clark, Jack Reed and Sam Nunn.]