Is there any particular reason why the email address should be included in the element of the the RSS feed? I know this is just to conform to the RSS 2.0 Spec, but it is an invitation to spam. It was a little unsettling to see that my personal email address has been in one of my discourse installs all this time. I’d recommend getting rid of the element altogether. I think most major CMS’s and blogging platforms do anyway.
edit: Maybe not get rid of it, but just the email address.