It is a proverb that an effective person chooses his or her battles. After letting so many things slide by (warrantless wiretaps, 750 billion dollar financial institution bailout, and so on) it is interesting that the Congress chooses to make a stand in the case of Roland Burris http://blogs.suntimes.com/sweet/2009/01/burris_may_end_up_as_illinois.html
To make a point "on principle" of not seating him based upon allegations against his nominator seems an odd choice to me. I think other issues of more substance would be a better use of the time of Congress.