Though the new Apple TV has gaming and app features, it's quite clear this is just a side business for Apple. But a successful one it will be.
Will it evolve to compete with XBOX and Playstation? It already has. The original Apple TV launched at around the same time as the PS3 and XBOX 360, and both of those platforms updated to support more media features so their value increased outside of gaming.
Apple is now doing the opposite. Now, it doesn't run the best SOC of the Apple product line, and it's controller doesn't have the type of motion tracking found on the XB1, PS4, or Wii U, but ultimately, most consumers don't care.
For the kind of consumer who NEEDS Netflix, Youtube, music, and photos, and to stream from their phone or tablet, the Apple TV is the best choice. And for those who want to play a game every once in a while, then it's over $100 cheaper than the next best competitor with the same media features(Wii U has next to none).
It's a niche, and Apple is happy to fill it. The questions isn't will it have games(as there will be thousands ready to play on it on day one), but whether the exclusive titles will be captivating, or if the platform can allow new types of gaming to proliferate that wouldn't otherwise be possible.