Chromecast and the idea that a TV is just a "dumb screen" is fairly successful.
VR might become a thing.
VR might become a thing.
>and what do I do with the TV I already have
You keep it. The Apple TV is a set-top device, not an actual TV.
Ah, sorry, did not know that. The name suggested to me that it's an actual TV. My bad.
Now I see, a set-top box does quite render a TV just a dumb screen. And similar devices/boxes/ideas did exist before, though severely limited by accessibility and expertise needed.
The Chromecast though — as I see it — truly presented that "just a dumb screen" idea in its simplest form. It's small, and thus ultraportable; it screams "plug me!" (into an HDMI port, that is); and makes that dumb screen accessible to a much larger range of people.
If I were to put it simply: Apple TV is to a Nokia Symbian phone, as the Chromecast is to the iPhone 1