It seems like earlier today, Apple has quietly pushed out an Apple TV 2G update that now brings support for purchasing TV episodes via the Apple TV itself.
I just ran software update on my Apple TV 2 and got a new update that adds support for a major new feature: purchased TV shows. You can buy - not just rent but buy - new episodes directly from your Apple TV, and access and stream any TV show episodes you've previously purchased using your iTunes account.Previously, it was not possible for you to purchase TV episodes via the Apple TV 2G. Not only this, the update also adds support for Vimeo video content and the YouTube playlist feature. Apart from this, Apple has also added Purchased tab under the TV section in iTunes for both Windows and Mac allowing you to free re-download content that you have already paid for.
This brings the Apple TV 2G iOS version up to iOS 4.3 with a build number of 8F455. Initial reports are suggesting that this Purchased feature is currently available in the U.S. as of now. Earlier today, we also reported that Apple may release 3 HDTVs by March 2012.