Not sure if this would help anyone else. I was getting a feedburner validation error where it didn't like:
<itunes:summary> </itunes:summary>
To fix this, I changed line 244 in podcasting-feed.php to read:
echo '<itunes:summary>' . str_replace(" "," ",preg_replace('~�*([0-9]+);~e', '',$itunes_summary)) . '</itunes:summary>' . "\n";
The feed then validated fine. I don't know if this is a bug or there is something specific in my settings but when I upgrade the plugin I have to put this back in or the feed validation fails.