I'm currently having this EXACT SAME PROBLEM.
I have a macbook,
apple tv shows up in devices,
i have custom sync settings - basically i'm not syncing anything at the moment, and i have the box unchecked for 'show only synced items'
i'm logged in on the same account in itunes and on ATV.
I can stream music, movies, and photos on my ATV, but no TV Shows.
Also, when I click on TV Shows under the ATV in iTunes, there's nothing. but when I click on TV Shows under Library all of them are there. All purchased from iTunes.
Maybe it'll be working when I get home from work? Perhaps it just takes time for iTunes to authorize the AppleTV