Maybe worth clarifying, the new TV is pretty much a stand-alone device. You can do AirPlay and stuff, like its predecessors - but it now has its own App Store with media Apps, Games Apps etc, so it does fantastic things even without any iPads, IPods or iPhones.
For games, you can use the Apple supplied Siri remote, or you can use compatible 3rd party controllers.
ATV aside, I personally think there is a future for Set Top Boxes vs Smart TVs. For the simple reason, technology evolves fast, and I want my big expensive flat panel on the wall to outlive the whatever 'fads' are current. I don't mind buying a new STB once every few years, but I won't buy a new LCD panel that often.