What makes it inferior to Apple TV? I own an Apple TV and beyond Netflix and Youtube I really have no use for it.
Forgot to mention that they'll open up their SDK so you can probably expect some cool hacks in the near future.
Making a remote-based, d-pad interface as convenient as a touch screen is very, very difficult.
I don't think "downloading a movie" is a use that they've shown or discussed. It seems primarily like a device for showing streams of video content from the cloud, with a secondary capability of mirroring a Chrome tab. It's not a miracast device; it's more like an AppleTV that you control from your phone or computer.