Say I have a series of tags (such as "travel", "Paris", "cheese") attached to a post or entry. Is there a standard way of listing those tags in an Atom feed? Even if there isn't, is there a de facto standard that is used by most feed readers?
Atom defines a 'category' element for general classification of posts. Theresa O’Connor's Representing Tags in Atom is a good summary of the ways this can be used for tags, with advice about benefits.