UPDATE: Fif appeared on the show's finale at L.A. Reid's request.
50 Cent is scheduled to appear on FOX's The X Factor tonight (Dec. 22).
Additionally, L.A. Reid, who tapped Fif for the gig, "still has a couple surprises up his sleeve," according to Billboard.com. Recent performers on the show include R. Kelly, Avril Lavigne and Alanis Morisstte, each of whom appeared on last night's episode.
UPDATE: 50 Cent graced the stage earlier tonight on FOX's The X Factor to perform "Wait Until Tonight" and "In Da Club." Watch the performance below.