There's an added twist, depending on how close Obama and Clinton end up. Edwards still has his delegates, and he gets to decide who they vote for (I believe). Which potential puts him in a position of being an even more powerful king-maker.

I'll be very surprised if this gets out of hand. Right now, it's all great shtik: everyone is waiting the their seats' edges over the Democratic primaries. By the time the convention rolls around, I'm sure Dean and the DNC will have made sure the candidates and delegates all know where they stand, and the loser will throw all his/her support to the victor with a smile (and I think both Obama and Clinton are good enough players that they will do that).