I've been soloing 25HC Cata bosses since SoO launched, and I'm not especially good at that. They really are not that hard two xpacs on, especially since the DPS boosting buff applies to Cata and earlier content. So, uh, that isn't gonna be the reason for a nerf.
Most of those changes have been about bots, and so mostly targetting repeatable stuff, too. Which means that trash drops before the first boss are gonna die one by one, but anything that is weekly locked? Not really a big deal, because 5k once a week is not worth much to a gold seller. (Like, $5, right.)