How are Laureates selected? | Nobels fredspris
Read the part about nominations, in particular how names can be added AFTER February 1st, and how "In the process, a need sometimes arises to obtain additional information and updating from the group of advisers, especially if any of the nominees are involved in current political affairs."
Obama's work since Feb 1st (some of which Eric posted above) has obviously been taken into account.
The committee "has been known not to arrive at a decision until at its very last meeting before the announcement of the Prize at the beginning of October."
But then again the link in post 9 was from the Daily Mail, and we all know how factual that particular chip wrapping is.