When the Apple TV first came out, this was a feature it obviously lacked (in common with the new Airport Extreme and now Time Capsule). After comparing it with a Mac Mini I went with the Mini, mostly for the DVD playback and EyeTV support; at the time this suffered a similar disadvantage, subsequently mitigated by the arrival of Airfoil 3 which offers comparable functionality on any Mac (even if you can’t select the Mini’s speakers directly from iTunes).
This official new feature makes the Apple TV look more attractive, although with no price cut in the UK to match that in the US and no movie rentals, it’s still not a killer proposition. Perhaps the more significant angle to this discovery is the fact that Apple haven’t forgotten about AirTunes.
So come on Apple, how about an AirTunes Time Capsule?