If Blizzard is dead set on no flying, then please, PLEASE create content with no flying in mind. Don't add in content same as usual; amend or alter them so that they accommodate the inability to fly.
This article that Lio linked explains how WoW has steadily shortened the stick upon which the carrot dangles. Not only that, though, but the tools to get to that stick have also been cut. Flying, for example.
When I read about the two new pets coming in 6.2 that will have similar if not same spawning mechanics as the Unborn Val'kyr, I was pretty livid. Not only did I not understand the logic (or lack thereof) behind it, but the fact that it felt like manipulation also upset me.
I gauge content and the desirability of it with the following (loose) equation. It's something I feel should be kept in mind when adding features and mechanics to the game.
RNG + Effort required = Willingness to participate
I say loose equation because 1 - I'm no math major nor was it my strongest subject, so I can't even say it's a proper equation. And 2 - the three things involved can be broken down into smaller parts. Perhaps it's more like a puzzle and these are just the three main pieces.
Anyway, to give an example of what I'm talking about, let's take the Sprite Darter Hatchling. Before and after Cataclysm, when the source of this pet was changed.