Apple as early as this fall may choose to test the waters for 1080p video sales through its ubiquitous iTunes service, as a handful of feature films being submitted to the iTunes Store for a release in the September and October timeframe are being sent with documentation for an optional 1920x1080 resolution, according to people familiar with the matter," revealed some sources to AppleInside.
"For instance, one such film from 20th Century Fox was said to have arrived with encoding options for SD (480p), HD (720p), and a new, third format listed as HD+ (1080p). Similarly, a small number of upcoming releases from two of the other 'big 5' movie studios were submitted with optional resolutions of 1920x1080 and an average bitrate encoding of 10,000 kbps."
According to these same people, there've been rumors inside the company of a new version of Apple's $99 Apple TV device under development that would be capable of outputting 1080p streams via an upgrade to the company's new A5 chip, unlike the existing model which can accept 1080p content but downscales all output to 720p due to the lack of horsepower in the device's first-generation A4 processor."
However, the story speculates that if Apple were to offer 1080p video via download it would do so as a direct download just for the PC and Mac platforms. 1080p files would certainly be much larger in terms of file size compared to the current SD and 720p HD movies that Apple currently has on iTunes.