I think where a company like blockbuster or even wal-mart (who just got into this game) can really take control of the market is if a company like Blockbuster ALSO had a warehouse like netflix that you could order hard to find titles from.
You log onto the website, lookup your movie, and they'll tell you if its in stock at a store close to you or if it needs to be mailed.
The bonus is when you're done watching it you can return it to the closest store to you OR mail it back. That way you can get another title right away without having to wait on the mail.
The only thing netflix has over the video stores is selection, so this would put the video chain that does it into a dominant position.
