SYSTEM OF A DOWN singer Serj Tankian performed the song "Empty Walls" on ABC-TV's "Jimmy Kimmel Live!" on this past Friday's (March 28) episode. Watch the performance below.As previously reported, Serj Tankian has been added to the lineup of this year's Coachella Valley Music & Arts Festival, scheduled for April 25-27 at the Empire Polo Field in Indio, California. With SCARS ON BROADWAY, the new band featuring SYSTEM guitarist Daron Malakian and drummer John Dolmayan, previously announced for the festival, speculation has started about whether the musicians will get together for a surprise SYSTEM reunion. The band has been on hiatus since the fall of 2006, with Tankian releasing his first solo album, "Elect the Dead", last fall. The SCARS ON BROADWAY debut is due out this summer. Malakian recently told MTV.com that SYSTEM's hiatus may be permanent, saying, "If anyone's holding their breath for a SYSTEM record, they're going to turn blue and pass out. It's a long ways away, if it ever even happens."