Neanderthals and Homo Sapiens interbred?

Darkman, Walkin Dude writes: "A recent Daily Mail issue has a fascinating article about the possibility that Homo Sapiens interbred with Neanderthals, which could be the reason for the mysterious disappearance of the Neanderthals some twenty thousand odd years ago. Could this also be the reason that white or pale skin and blonde hair originated in northern Europe, and nowhere else?"