Timberlake fueled the rumors with a tweet. It reads, "Thursday, January 10th, 2013 at 9:01 am PST..." So, by lunchtime in the east on Thursday, we should know what is going on. The two superstars have attempted to work togeteher in the past, but nothing has ever been released.
The announcement from Timberlake came in the form of a one minute Youtube video. The message is essentially, "I'm ready."