Maybe I missed something, but I'm fairly certain that Apple doesn't consider the ATV2 an iOS device. We all know that the ATV2 runs iOS, but Apple seems to group only their mobile devices under the iOS umbrella.
That being said, I think iOS 4.3 is going to be big for ATV2. One quote from the advertising on the Apple site that I particularly liked was , "Airplay Enhancements - ...even Airplay-endable apps and websites get the big screen treatment with iOS 4.3..." Vague, but promising.