I have both 1 Roku, and and 2 Apple TVs. I wish I had 3 Rokus instead. Plex alone is such an amazing application worth buying the Roku for. Thanks to Apple's closed environment they're leaving themselves behind not allowing people to build Apps for the ATV. Apple's belief in not building cross platform is also a self-stabber.
It's probably never going to happen, but if they built apps for Android, they would open the door, allowing other mobile devices to control their hardware. I don't have an iPhone anymore, and I can't control my Apple TV, unless I buy some hacked app to talk to it or use the Apple TV's crappy remote, and there's no way I'm typing with it. Roku however, built apps for multiple platforms to control it's device.