Along the introduction of a 1080p-capable Apple TV, Apple released iTunes 10.6 on Wednesday. The update added support for playing 1080p resolution videos from the iTunes Store.
iTunes 10.6 adds 1080p video support
The 10.6 update also improved song matching, album artwork handling, and fixes an issue where songs played through iCloud could be accidentally skipped.
iTunes 10.6 is free and available via the the Software Update application, or as a downloadable installer at the Apple website.