Generally speaking, I think most games are leaked early by the dastardly pirates. I would have expected it to be a torrent of one of the copies given early to a reviewer, or a copy some employee at a game retailer swiped from the storage room, rather than a steam pre-load. Im not even sure what value pirating the pre-load content would have, unless someone is working on a crack so people can play it without alerting valve. I'm sure someone will see this thread and be able to enlighten me though.