No need to toss in a man of straw here. Anyone who's been aware of text-sharing sites since such things existed, knows that the abuse (copyrighted, illegal, ill-gotten material) far exceeds "legitimate" use. In fact, one could argue rather easily that MegaUpload had several magnitudes more legitimate use than pastebin.com (and similar).
The typical structure of an mysql dump is a rather easy thing to automatically sense. A not-complicated regex could easily sense the pasting of alternative formats. Mr. Vader could easily reduce his workload in dealing with takedowns by simply injecting a little code that preemptively enforces his terms of service.
Long text with reporter bylines, also easy to sense.
Really long text with bibliographies, also easy to sense.
I could go on. ;)