Even if it is the same file if the provided links are private I think they should be safe under how DMCA is worded. Each link can be considered a key to locker and it would not be Megaupload's job to know who should have a key and who should not. DMCA would require them to reject keys but not necessarily the locker under many situations.
My previous post:
http://news.ycombinator.com/item?id=3486903
