Hey guys, so i came across this addon in my wowaceupdater. its called Omen.
http://wowace.com/wiki/Omen
imo it works better than ktm threat meter because is more lightweight and doesn't use threat aggregation allowing more accurate threat calculations when fighting bosses with adds. there is a good explanation in the link there. if you don't use wowaceupdater then you can download it directly from http://files.wowace.com/Omen/Omen.zip.
also if you haven't found the glory of ace'd addons i recommend them highly. and if you haven't submitted to the wonderful being that is wowaceupdater i recommend you do so as well.