Jennifer Lopez Back on Island

JENNY BACK ON THE BLOCK: L.A. Reid's latest IDJ signing, American Idol judge Jennifer Lopez, is proving to be another shrewd move as her "On the Floor" single debuts at #9 on the singles chart, with the video premiering on the high-visibility American Idol tomorrow night. J. Lo last appeared on the chart with "Do It Well" back in 2007, which peaked at #31. (3/2p)