markci,
I had this problem too. The Apple TV menu has two episode menus: One is labeled 'All Seasons' which was my default. New episodes were only showing up on this menu after ONE WEEK. It frustrated the **** out of me to the point I bought a Roku to stream the latest episodes from Amazon.
Anyway, If you choose 'More in the iTunes store', it will bring up the 'normal' season list with the current episode releases. I'm a huge Apple fan but they've really screwed the pooch lately with some poorly desgined options, and unfortunately they will lose some business in frustration like mine because of it.
Mike