(May have already happened today, I haven't turned the tv on yet.)
It is a tough pick for Crist because he has/had already announced plans to run for the seat that Mel Martinez decide to quit on. So whoever gets the pick will be his major obstacle in one year when he decides to run.
Put someone good in there and he might not win the seat if they decide to stay and run themselves.
Put someone bland in there that he can beat and it could be used against him by his opponents and make him look weak and ineffective.
Dude got a mess on his hands either way.