I don't know about that. Nothing like a major motion picture or TV series has ever been platform-locked, has it? Video games, yes, but not traditional "mainstream" entertainment.
NFL is locked in. Should be interesting to see when they make the move to online. There is currently no way to watch NFL online in the US because networks pay a LOT of money for exclusive rights. With the amount of cash Apple has on hand, for example, we could see some huge shifts.