I think Obama's grand plan to have this announcement be the leading story for the 5/6pm o'clock news went awry because some of the people higher on the list than Biden turned him down.
Here is what I think happend.. Kaine turned him down.. Richardson turned him down.. Bayh turned him down.. That is why I think it took longer than expected to announce his pick..
I think you are correct about Obama not getting his first and probably second choice if not more then that and why everything was delayed. Last night was one of the funniest nights I have had on here.