Apparently, The CW has pushed the returns of Supernatural and Smallville. Here's the press release...
On Friday, January 28, (8:00-9:00 p.m.) an encore of The Vampire Diaries episode titled "The Descent" will air in place of the previously announced Smallville episode titled "Collateral".
On Friday, January 28 (9:00-10:00 p.m.) an encore of the Nikita episode titled "Free" will air in place of the previously announced Supernatural episode titled "Like a Virgin".
Related: Arrow, The 100, Flash, Supernatural & More Renewed at The CW
Both Supernatural and Smallville return with new episodes on February 4th, 2011.