Sometimes the iTunes Store can't publish certain podcasts. If you've submitted a podcast using the "Publish a Podcast" page but haven't seen it published yet, sit tight. The iTunes team reviews each podcast submission. Depending on demand, it may take a week or two before the podcast gets published.
Additionally, here are some other reasons why a podcast might not get published:
If you are the podcast owner, make sure that your podcast is available on the Internet. Your podcast's RSS feed should also conform to the iTunes extended podcast RSS specification.
If you are not the podcast owner, please contact the podcast owner and direct them to our specification page.