I think he's doing a helluva job
Since then, Burris has appeared at rallies and campaign events for Blagojevich as recently as June of this year long after it was common knowledge that he was being seriously investigated for corruption. In April of 2006, he was one of the hosts for a campaign fundraiser for Blagojevich.
Yet, it is some of the business dealings that Burris has had with the state that maybe of most interest. A consulting company he lobbied for received a $150,000 contract from IDOT (the Illinois Department of Traffic) to advised disadvantaged businesses on turning their operations around. (this the Illinois GOP seems to think is an indication of pay to play though that appears to be a bit of a stretch to me) He lobbied on behalf of Ho Chunk casinos when they applied to get a license in the suburb of Hoffman Estates. A company that he lobbied for was investigated for fraud in Nevada, and this investigation caused said company, ACS, to have their contract withdrawn at the last minute by Cook County Board President Todd Stroger.
All of this is not necessarily a mountain of evidence of fraud and corruption, but given the circumstances, it should give all political opponents a field day for making the case that Burris can't be the next U.S. Senator from Illinois.