West Virginia to Big 12, Missouri to SEC (imminent)

[Will94]

West Virginia University To Join Big 12 Conference - Big 12 Conference - Official Athletic Site

Beginning with the 2012-13 season it is expected that the Big 12 Conference will be comprised of 10 Universities – Baylor, Iowa State, Kansas, Kansas State, Oklahoma, Oklahoma State, TCU, Texas, Texas Tech and West Virginia. The Big 12’s footprint will encompass five states with over 36 million people. More than 4,100 student-athletes from across the United States and around the World compete annually in the 23 sports sponsored by the Conference.

Notice that Missouri is not listed.

Last night the SEC put up this announcement on its website (notice that it's dated 10/22... oops).
Tiger Tracks: Missouri Joins The SEC > SEC > NEWS

BIRMINGHAM, Ala. – Given the ever-changing conference paradigm over the past year, the Southeastern Conference has continued to demonstrate its commitment to maintaining its stature as one of the nation’s premier conferences by welcoming the University of Missouri as the league’s 14th member, Commissioner Mike Slive announced Monday.

Missouri joins Texas A&M University as the league’s two new institutions who will begin full membership on July 1, 2012. It is the first expansion of the SEC membership since Arkansas and South Carolina joined the conference in 1992.

Missouri was a charter member of the Missouri Valley Intercollegiate Athletic Association in 1907, which became the Big Six Conference in 1964, the Big Eight Conference in 1964 and the Big 12 Conference in 1996.

The conference has since removed the posting. I am guessing that they want to wait until after tomorrow's Missouri at Texas A&M game to make the announcement.