The Washington Post reported:
"Treasury Secretary John W. Snow, who has presided during a period of strong economic growth but at times seemed out of sync with President Bush, has informed the White House that he will resign in the coming days after three years as the nation's chief economic officer, a source close to Snow said..."
Read the story here.
Apparently, being a student of Nobel Prize winner Jim Buchanan back in the 60s at UVA did not help Snow keep his job. Here is an old story which mentions John as Jimmy Buchanan's student.