Most of the TV shows available from iTunes can only be purchased, not rented. The new Apple TV can only rent. Thus, most shows from iTunes cannot be obtained directly from the new Apple TV. You can watch them, but you have to buy them from a Mac or PC with iTunes, then play them on Apple TV via home sharing. The new Apple TV would be a much more appealing proposition if all iTunes TV shows were available to rent. The decision to make more shows available to rent belongs to the networks, not Apple, but Apple’s the one that decided to sell a new Apple TV that can only rent content.