FeedBurner is an awesome service that hosts millions of RSS feeds, so it's understandable that they're a little busy.
Every once in a while, a customer contacts us about their iTunes feed not getting updates, and they happen to be using FeedBurner. While FeedBurner should update every 60 minutes in accordance with the settings we render in your RSS, they seem to ignore that and refresh whenever they get around to it.
To manually force FeedBurner to update your feed, go to this page and enter your FeedBurner URL. Within the next few minutes, they will update their copy of your Hipcast feed on their servers.
Additionally, to confirm your RSS is being generated properly by Hipcast, you can disable the FeedBurner redirect by adding ?redirect=false to your Hipcast RSS URL. Here's an example (not an actual feed URL):
What you should see is the RSS for your feed with the latest updates included, verifying that we are indeed providing your latest changes to FeedBurner.