The latest 4th generation Apple TV from Apple, was a great successor. This created a new opportunity for Apple to bring apps to the TV screen and created a new place in the home entertainment sector for Apple. Although google tried to create an App market with the Nexus player, it did not see the same amount of success. The same cannot be said for the Google Chromecast, which has multi-platform support and created a new market for google in the Budget Streaming devices.
Back to the Apple TV. Unlike its predecessor, it does not have an Optical out port, rendering it not useful for an Home Theater system nor does it have an 4K model. Although some might say that 4K and UHD are still not standards, it could have been a good upgrade. But the new TV has Siri, an improved (but sensitive) remote, an App Store and a more optimized OS for a TV.