Except for the amount it embarrasses his bumbling administration, I can't imagine Obama really being all that upset by the antics of Julian Assange. 'Course he'll have to throw him under the bus, but it seems to me like the sort of a stunt a community organizer would admire.
From Robert Gibbs:
"It is safe to say that the president was, as an understatement, not pleased this information becoming public,"' Gibbs said. "As you saw during the presidential campaign and as during his time in the White House, open and transparent government is something that the president believes is truly important."
"But the stealing of classified information and its dissemination is a crime."