I normally offtank this fight as a warrior and put my 2nd tank (Druid, pally, or DK) up as the main tank, even if they are slightly less geared.
I do this because:
1) intervene with safeguard talented is an awesome ability. I have helped prevent more wipes on this encounter with that ability alone than I ever thought I would.
2) It basically garuntees that I will have shield wall / last stand available for the frenzy in the case that the MT does die. I can simple taunt off and pop my stuff and buy the raid an additional 10 seconds or so.
3) I can put Vigilance on the other tank for a 3% damage reduction when BoSanc isn't available.