Obligatory warning: This script has been designated as an obsoleted "Retro Script". There is no guarantee that it will function as described with modern versions of iTunes and OS X. If used in its current form it may not work at all without modification and, at worst, it may corrupt or destroy data.
iTunes will stop updating a podcast if you have not listened to at least one of its episodes in five days. This script will batch-update every podcast subscription so you don't have to manually update each one individually.
I have posted instructions on how to create a launchd agent to run this script automatically and invisibly in the background to ensure that your Podcasts are always updated.
Possible iTunes bug (July 17, 2014): Looks like the iTunes AppleScript command updatePodcast command is broken as of iTunes 11.
downloaded 5m 16s ago
Remove iTunes tracks disassociated from files
downloaded 12m 24s ago
Set the Album Rating for the album of a selected track to full- and half-stars or computed clear-stars
downloaded 13m 5s ago
Sort purchased tracks into discrete playlists by name or Apple ID
downloaded 17m 50s ago
View/Edit tags of selected track(s) in single window
downloaded 19m 28s ago
Set current track's start or stop time to current player position
downloaded 23m 5s ago
Change file type to make selected AACs bookmarkable