After weeks of waiting, there's finally some info on Destiny's raid challenges. Apparently in early December, they will be available for normal and hard mode, and will buff a different boss every week with a new strategy to deal with. You'll be able to see the boss that has been altered before you enter the raid by way of a skull on the Director screen, which will impact both difficulties.
They aren't giving any details, but hint that the single-pool strategy for Golgoroth may not work out so well. I think I have an idea of what to expect here, I just hope the rewards are actually worth it.