Favorite podcast plugin

We have a media site at http://www.holyculture.net and we currently send out podcast to itunes from blogger.com and we'd like to get away from doing that. That challenge I see is that on our media site we have a lot of audio files and not all of them are podcasts. So I am looking for a way to selectively pick which audio files are podcasts and only have those go up to itunes.

From what I have seen, it is an all or nothing scenario coming from your RSS feed through feedburner. Has anyone seen another scenario via a plugin or something to better control that?

Thanks
James