The first is in response to some feedback about what the devs yesterday called "binary" hard modes -- they said that instead of providing multiple levels of difficulty (as in Sarth and his drakes), they'd prefer to have a hard mode either on or off (you'll be able to toggle between the two in Icecrown). This relates to what we just said recently, with different types of guilds looking for different types of content to play. GC replies that the "in-betweens" in terms of difficulty will come with later bosses in normal mode -- if you want to play a challenge without stepping into the hard modes, Blizzard will do their best to make sure that the last bosses on normal give you that challenge. Which makes sense -- bosses should ramp up in difficulty as the instance goes along, and no one would suggest, for instance, that Yogg was nearly as easy as Flame Leviathan.
And GC also talked about one of my favorite (and missed) game mechanics: crowd control.