Perhaps 4K streaming on the way? Seems they've been working on it for a while.
From 2010:
Apple moving towards new video codec?
Rumor: Apple to launch 4k video format?
Rumor: Apple Moving to 4K Video
From earlier this year:
Apple working on improved media streaming engines
Ohhh gawwd, displaying 4k?
then we have to overshoot @ 8k
http://upload.wikimedia.org/wikipedia/commons/7/79/8K_Camera_(2009_version).jpg
Although, commoners can't tell the diff between 720 and 4k in a theater...