Drkshadow posted in the official forums with what he considers a slap in the face for folks looking to use their flying mounts in Northrend. (It's always a slap in the face, isn't it?) The quest to "attune" your mount to Northrend has been removed, and replaced with a simple 1000 gold payout. If you don't pay, you don't fly.
Bornakk confirms the change only a few posts later. He says turning the attunement into a cash payment makes it easier for more players to get. It might suck to pay the 1000G for each hungry alt. But, really, if you consider it -- how hard is it to farm up 1000G on your main? I think Bornakk makes a fair point -- it's probably easier to just grab cash on your main than take a relatively undergeared alt through a quest over and over.
Of course, we already knew that flying wasn't going to be very expensive. I guess someone might argue that 1000 gold can be a lot of cash, but that's really only a few days of dailies, or maybe a quick trip to sell loot at the auction house. At level 80, I'm just not going to get intimidated by a single grand.