I understand why people think that Fitzpatrick went public “early” to protect Obama, Emanuel et al., but don't forget that it has been reported that the Chicago Tribune had been sitting on the story for some time and that it had decided it was no longer keeping it underwraps but was going to publish the story.
This is the primary reason why Fitzpatrick arrested Blago. He didn't want to get scooped by the Trib.
However, a decent D.A. can indict a “ham sandwich” so I think that there are some maneuvers going on under the radar.