Hearthpwn

I think with the current expac. you're seeing quite a few non-Renethal decks.  Admittedly these tend to be OTK or aggro (or Rogue shennanigans), but nonetheless highlight the drawback of Renethal which is the lack of conistency (which is actually bigger than you think, it just doesn't seem that way you play against a deck which still seems to have the answers).

There is definitely an argument to HoF him as he has become quite prevelant, but I think the main issue is the power level of the early game that makes him essential if you're not playing aggro.  You can still easily die by turn 6 from 40 health...