They'll probably come up with some technology which will make their films unviewable on the Internet, or the distributors may even absorb search engines--a Time/Warner/Google mega-corporation seems likely soon...
Studios tried hard to add copy protection features to DVD's and CD's but crooks always found the key. Their decision to go after the users has been bearing more fruit.
The only defense that internet providers have is to be able to show that they actively shut down illegal streaming whenever they saw evidence of it and did nothing to facilitate it.
That's why companies like chess.com have to close any links to Pawn Sacrifice (or other valuable copyrighted material) and kick out those who continue to post those links after warnings.
They may legitimately be able to ignore links to old movies because studios don't pursue those as actively since it is harder to claim big damages for movies that aren't earning anything sitting in their vaults. (I don't know for sure.)
It still retains it's door-hood:)