Bieber Julkeyz

THRILL RIDE: It certainly has been a "Roller Coaster" on the iTunes chart today; before being surpassed by A Great Big World's "Say Something," the new Justin Bieber song "Roller Coaster" occupied the #1 spot on the singles side. The song, co-written by Bieber and Julkeyz (aka Julian Swirsky, who co-produced with Rodney Jerkins), is the latest in the Island/IDJ star's series of weekly singles. (11/25p)