Love him or hate him, Timbaland has been one of the most influential and prolific rap producers of the last twenty years, and you could do a lot worse for a producer to spearhead the upcoming posthumous Michael Jackson release Xscape.Posthumous releases are nothing new. Tupac Shakur has released more material since his death than he ever did in life, new tracks from Biggie are popping up now and then, and studio outtakes are frequently used to create whole new tracks by fans and professionals alike.The fact is that when you're a recording artist, you only use about ten percent of what you put down on tape, if that. Some producers may be a little more efficient than that, but others are like Stanley Kubrick in the studio, recording thousands of hours of material for a fifty minute album. So it's not surprising that the biggest pop star of the last fifty years has more than a few extra vocal tracks laying around.Timbaland will be spearheading the Xscape album based on this material, along with Rodney Jerkins, Stargate, Jroc and John McClain, producing new tracks from unreleased content, as well as "contemporizing" classic MJ tunes.The project has generated cynicism and anticipation in equal parts. It's exciting to know that new Jackson songs are on the way, but some wonder if his classics really need to be "contemporized." Timbaland has proven himself an able producer of danceable tracks, and while it's easy to be down on the project, fans may be surprised at what Timbaland and co. can do with raw, never-before-heard MJ vocal tracks.In any event, the album is set for a May release. The new disc is sure to make an impact on the charts, but only time will tell if the new tracks can stand beside Beat It and Thriller.