When iTunes first added podcast support, there was no way to make a Smart Playlist of podcasts. This was solved soon afterwards with an update. I am now hooked on podcasts, and listen to them weekdays at work. I created a smart playlist based on "Date Added in the past 1 day," so I could sort through the most recent podcasts. I also had playlists for the past two days, past three days, etc.
On Monday mornings, I'd find myself with a ton of podcasts from over the weekend, and often would not be able to get thru them all. It was then cumbersome trying to sort thru everything from the past four days, when I may really just be wanting the ones I missed from four days ago. I really needed something that said "show me podcasts from just three days ago." I finally realized there is a way to do this. Create a Smart Playlist with the following conditions:
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