My Guess

My guess is that Hilary Clinton will be allowed to say she declined the position of Secretary of State.

Obama Upside
Party unity is restored.
He gets to look like a peacemaker. (see Lieberman)
He gets Bill Richardson as SoS.

Hilary Upside
She doesn't have to manage the snakepit at State
She gets the bump "Just to be condsidered."
She can blame Bill for her declination.
Since SoS is rarely a two term job she can stay in the public eye until 2016, the next realistic opportunity for a Presidential campaign.