HBO Go and ESPN recently got added to the Apple TV, but only if you pay a hefty, monthly sum to a cable or satellite company for a bunch of other channels you never watch. The TV industry is evidently broken. You can have unlimited access to stream HD content for the price of a couple cups of coffee each month, but you can’t pay for HBO a la carte.
The Apple TV is slowly but surely becoming a more formidable media player with the addition of apps like HBO Go. But developers still can’t create apps and submit them to an Apple TV App Store; Apple handpicks partners to work with.