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/or macOS. 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 6m 37s ago
Exports and then re-imports selected tracks' artwork
downloaded 29m 45s ago
Copy files of tracks to selected folder
downloaded 37m 4s ago
Use tag data to formulate new file name for selected tracks' files
downloaded 1h 21m 46s ago
Perform search-and-replace on text in your choice of tags
downloaded 1h 42m 48s ago
Batch-change the Album Rating for the albums of selected tracks
downloaded 2h 49m 28s ago
Copy chosen tag info from one set of tracks to a different set of tracks