As pointed out by AppleInsider, Apple has changed the terms and conditions of the iTunes Store with a reference to Apple TV software version 3.0.
The new paragraph in the conditions under the header "iTUNES LP AND iTUNES EXTRAS" refers to the Apple TV and reads: "iTunes LP and iTunes Extras Products are usable only on computers with iTunes 9 or higher and Apple TV with software version 3.0 or higher."
It is apparent from this that the 3.0 software update for the Apple TV will bring iTunes LP which was introduced in September alongside iTunes 9.
The latest software update for Apple TV brought the version to 2.4.