According to Bob Nightengale, the White Sox will promote Ken Williams President and Rick Hahn will replace him as the team's General Manager.
Williams has been the Sox GM for the last 12 years, building the team that won the 2005 World Series and this year's Central Division leading club.
His tenure as GM has been... interesting, to say the least. He made a gamble that, at the time, appeared to be a biblical failure when he put a waiver claim on Alex Rios. However, this year Rios has been a revelation and a key part of the team's success. He also paid big money for both Jake Peavy and Adam Dunn, with varying results to date. Many Sox fans point to the (not one, but) two trades of Gio Gonzalez as the worst move of Williams' time as GM.
Hahn has also been with the Sox for 12 years, and was a hot name last winter when a couple organizations were looking for a new GM of their own.