CommenterUsername
This template tag returns the username of the current commenter in context. If no name exists, then it returns an empty string.
Example:
<mt:Entries> <h1><$mt:EntryTitle$></h1> <mt:Comments> <a name="comment-<$mt:CommentID$>"></a> <p><$mt:CommentBody$></p> <cite><a href="/profiles/<$mt:CommenterID$>"><$mt:CommenterUsername$></a></cite> </mt:Comments> </mt:Entries>