Make changes to the following and paste it into your template so that you can track all of your subscribers:
read more about it:
Converstations: Are Your FeedBurner Feeds Discovered?: "the auto-discovery doesn't see the FeedBurner feed, only the default Atom and RSS feeds. If Steve is tracking numbers with FeedBurner, it's not accurate.
If Steve wants all feed discoveries to see his FeedBurner feed, a simple adjustment to this code in his 'head' section will do the trick."