Melson's replacement is B. Todd Jones, the U.S. Attorney for the District of Minnesota.
Jones first served as U.S. Attorney in Minnesota from 1998 to 2001. He sat out the Bush administration, as a partner at Robins, Kaplan, Miller & Ciresi in Minneapolis specializing in complex business litigation and corporate criminal defense.
Jones was confirmed again as U.S. Attorney in August (ed. 2009), and shortly thereafter Attorney General Eric Holder tapped him to chair the AGAC, a powerful policy body that meets with top department officials about once every six weeks. (SOURCE)
From the looks of Jones' bio, he appears to be a partisan hack. Originally a Clinton appointee, he took a powder during the Bush years, only to come back once Holder and Obama took the reins at DOJ. I do not like how this is unfolding. Traver is unable to get confirmed. So instead, they bring in a dark-horse nominee with strong Leftist chops. Kind of makes one wonder what happens next at ATF...
Melson story at POLITICO
B.Todd Jones info from MAIN JUSTICE
ETA: More from Main Justice about Ken Melson, and Dennis Burke, two figures who are central to the Gunwalker Scandal and cover-up.