It's best to get a plan in place and stick to it.
Obama needs to take questions from the press on the Blagojevic matter, and the sooner the better. First, find out from the entire transition team who knew what and when, then go forward and get all the information out there. Of course be careful not to say anything that would jeapordize the governor's presumption of innocence.
After the presser, Obama should then appoint a dedicated communications staffer to this case. Then, in all subsequent press briefings on other subjects (like governing for instance) Obama can refer all press inquiries to that staff person. Make one person the expert on the case and let them be the sole mouthpiece. It frees up the rest of the team.
All of the above just a suggestion, Mr. Gibbs. Love ya. Call me if you need any help.