"Although you select content on your device, there’s no AirPlay-like streaming going on, no bits flowing between your tablet and your TV. Once you start something playing, you can stomp your Android phone under foot and the video will continue on its merry way." Doesn't that make more sense than streaming something to your phone/tablet only to then use Airplay to stream that media to the AppleTV? Seems silly to doubly tax your wireless network.
If you never wanted to show something from your device other than streaming video, then it might be silly. But there are plenty of people who, for instance, preview presentations from Keynote on their TV sets with Apple TV. Those who think you can do that just as easily by plugging into an HDMI dongle and cable have almost certainly never tried both.