Don't take this as a definitive answer as it is SkepticOverlord who is working on the Podcasting feature, but I would assume this new system works
similarly to the forums in that once a post is made, it can not be deleted.
It's wonderful that you've made that picayune point MA.
There is currently no feature to remove your podcast from the feed. However, we are assembling a team of "PODmods" who will be able to disable a
feed item which amounts to the same thing. (There are assorted technical issues with the willy-nilly removal of RSS feed items.) For now, just send me
a u2u with what needs to be done.