I have just tried to rent Iron Man, first on my MacBook, but then for some reason the AirPlay button dissapeared when I tried to AirPlay it to my new Apple TV. So then I just decided to rent it straight on the Apple TV (3rd gen) and I had 2 free rentals from a previous problem, the rental on the MacBook used the first credit, and bizarrely the rental on the Apple TV used the 2nd, so I guess I would have been charged twice.
But now, after all that, it says ready to play in 8 hours 40 minutes. Which is quite unacceptable. When I was renting on my Macbook the total download time was around 8 hours. But I could start playing after about 15 minutes and it would download in the background.
Does the Apple TV not allow buffering, and require the whole movie to download before it allows you to start playing?
I'm really hoping I've missed something, because I'm beginning to wish I'd bought a Media Center PC.