One of the issues that Podcasters who have been podcasting for a while are starting to face is that feedburner has a limit to how big your RSS feed can be. When this happens your new shows fail to show up in your RSS feed.
I found this out when all the sudden my downloads got cut in half.
If you go into your wordpress and go to settings, then click on Reading. You can limit the number of posts that show up in your feed. Mine was set to 200. I set that to 100, and went into Feedburner and went to troubleshootize, and then did a resync. It's fine.
The effects of this is when a new person subscribes to the podcast (Building a Better Dave in this instance) they only see 100 (keep in mind many podcasters never make it past 7 episodes).