Tunes Listings for Podcasts are updating slowly
It’s a known problem at apple. They are having issues keeping listings updated. They know about it and are working on it.
The iTunes store listing and what appears in your feed are two different things. People that subscribe to your feed in iTunes will get the new episodes as you post them but the listing at iTunes can lag by a few days (or up to a week or so) behind your feed. This is normal.
People get the wrong impression that your RSS feed PUSiHES to iTunes. It does not. iTunes (when it sees fit) PULLS your feed. It asks for your feed when it gets around to it and PULLS your feed to update your listing. Your subscribers (even in iTunes) subscribe to your feed and after that never really touch iTunes (the service) again. They are just subscribed to your feed directly in the iTunes software. As long as when you publish an episode, you get it if you are subscribed, everything is working. It works the same as every other directory or app.
There is nothing we or you can do to make that faster. It takes whatever time it takes and if you want it to go faster you have to go to iTunes and refresh your feed manually.