This may just be me being dim, but what on earth makes YouTube worth so much money to the otherwise usually sensible Google?

To be sure, it currently has lots of users, but there's nothing special about the technology (see clones like pornotube.com) so the only barrier to entry is the bandwidth bills.

Is this the new way to get rich? Get other people to steal content (much of what's on YouTube is of doubtful legality), run up some enormous bandwidth bills and hope that someone comes along with an offer before the bank calls in the overdraft?