Two quick comments, having just tanked him on Heroic a couple of times

(1) Shadow priests are a good choice for taking (one of) the debuffs, because they can drop VE and, with the debuff, end up healing the whole group in the order of 400health/second or more (they can take down the one of the adds each wave with Shadow Word: Death)

(2) As a druid tank with a paladin healer, I simply hit barkskin / tranquility when he did the Overload, kept the group alive nicely.