John Gruber at DF read to TOS in the new iTunes and came up with this:
So there you have it, HD movies only available on TV. He found other interesting stuff, too. I suggest you read the whole article...
Here's the link to his article
Man, that would be a real bummer - there is no difference between downloading it to the AppleTV and to the computer, why would they restrict the HD to the AppleTV??? I would have to see some evidence of this before I believed it... (not that they wouldn't do something like this...)
I thought he said the whole point was that you could finish watching it on another device (like another computer???)
Because of DRM/HDMI. Your computer doesn't have an HDMI connector; an AppleTV does.