She was as gracious as someone who probably still thinks she would be the better candidate could be. As far as strategy goes, to be as cynical as possible, she will likely campaign as hard as she can for Obama while secretly hoping he will lose to McCain. Publicly I imagine she'll try and be the most enthusiastic supporter in the coming months, without overshadowing him, while consolidating her position within the party and the Senate - and in the event that Obama does lose - try to serve as a central figure for the party to rally around.
That hope - if she does hold it - is rather slim. Althought that while 80% of the US thinks the nation is heading in the wrong direction, and around the same amount disapprove of Bush, and that a lot of people do identify McCain with Bush the Presidential race is still neck-and-neck... is rather astounding.
I think your probably spot on. She hasn't given up on the White House and there is a good chance Obama could still loose, on that basis I think it may be wise to steer clear of the VP spot.
Then again, if he does win being a VP could be very good for her.
Of course if he wins, turns out to be a terrible President she might be better not being his VP...
She has a lot of thinking to do.
On further analysis, she probably won't be his VP - or at the very least he won't choose her. It doesn't guarantee her supporters and it would undercut his message of "change" to his supporters if he were to bring on his "establishment" Primary opponent. Also despite smiles and handshakes and kind words, imo, in actuality they really don't seem to particularly like each other.
Additionally strategically for her, if Obama does well she'll be 68 by the time his terms end almost as old as John McCain is now (polling shows a substantial voting bloc thinks he is too old). If he does poorly then the prospects of a Democratic bid would also be poor.