The site map module is not honoring the input filter settings for vocabulary descriptions. If you set your input filter to "Full HTML" when creating a description for a taxonomy vocabulary, the html code will show on the sitemap overview page for that vocabulary. This is because the html tags are being converted into html entity format before display.
It will display iike this:
<p>Here is some paragraph which is first.</p>
<p>Here is some paragraph which is second. I shouldn't be seeing these html paragraph tags -- but I am because they've been converted to their html entites like >p< </p>
The site map module should honor the input filter for the vocabulary description field.