I'm not sure about how others feel, but I just ment so it would stand out as members scroll through posts. Why? People will remember and to remember others mistakes will help aid in keeping others from walking down that dark path.
Remember, the more you kick the person for what was done, the more they could possibly try to cause problems here in the future if you know what I mean...
I really don't think simple red text would be wrong or below the boards standards. IMHO
.... now maybe if we have a drawing and divide up his post count with others 
that would be wrong.