I put this in the email - but will repeat here for those wondering:
There are two key reasons I see that make managing your feed on Wordpress a bad idea. This based on many users with one or both of these issues.
1. Feed bandwidth. As your feed grows in size you can actually have a bigger bandwidth usage for your feed then your media files. Your feed gets pinged (downloaded) many times a day by each subscriber. A feed that is 0.5 mb getting pinged 10 times a day 7 days a week will draw down 35 mb in bandwidth per user. While a new episode 60 minutes long once a week may only draw down 30 mb a user.
This becomes an issue as your show gets even moderately popular as this bandwidth is coming from your website host. We have seen many shows get their website shut down for this excess bandwidth. And if your website host says you have unlimited bandwidth what you really will see in the fine print is that they have a "cpu usage limit" and this is what they get you on. The goal of a podcast is to help promote your website not to shut it down.
This is why almost none of the top 200 podcasts in iTunes use Wordpress for their feed.
2. 3rd party plugin issues: the number one reason for using Wordpress is without a doubt to use the plethora of 3rd party plugins. Sadly however 3rd plugins can and often break your RSS feed when managing on Wordpress. There is no warning and if you don't catch it quick enough you can get your show removed from iTunes if the feed is dead long enough. Having a feed that can break any time you add a 3rd party plugin means you really do not have control of your feed.
Rob W