Maybe there's something to this World Wide Web fad after all. Well, anyway, the old boys at Viacom seem to think so. They've got this SVP Jason Witt fellow leading a new group called Digital Fusion. It's devoted to selling ads against MTV content on the information superhighway. Credit Sumner and the boys this much: They know their trends when they see them. But maybe they went too far out on a limb on this one. As Viacom studio execs keep telling striking writers, there's no money in online advertising. (photo by Joe Crawford (artlung))