It would be cool if there were a Podcast Subscription application. Currently you can download podcasts but you cannot subscribe.
Be really nice to extend the podcast functionality. Perhaps auto-update/download in the middle of the night the new ones from your podcast favorites? The appletv stays on all the time, the computer w/ external harddrive does not… maybe Apple will do this eventually… I use appletv for podcasts extensively… esp. video podcasts now that I have this: