WowAce

(This may well "supersede" ticket #15 (http://www.wowace.com/addons/pokedex/tickets/15-separate-flying-ground-hot-mount-selections/), but it's a rather more extensive change so filing a new ticket instead of hijacking my own previous enhancement suggestion.)

What is the enhancement in mind? How should it look and feel?
With Warlords, every flying mount can be used as a ground mount even in no-flying areas.  There are two (admittedly rather minor) flaws with this - 1) This makes ground mounts that much less likely to be randomly picked even if you mess with weights to try and counteract the sudden inflation of number of options, and more relevantly 2) Quite a few flyers either look noticeably less impressive or downright silly on the ground.

Therefore I suggest separate weights for ground/flying, at least for flying mounts (bit silly to have two copies of the same variable for ground, though it might end up simpler under the hood because programming can be weird like that).  My initial notion would be for it to behave like like the per-character rank override but on a profile-wide basis, that way only people who want to fiddle have to mess with the extra complication, but I'll admit to not having poked at the code.

The Favor Ground Mounts checkbox already gives most of you want - it filters mounts that can fly out of the ground mounts selection. That way, you only will get ground bound mounts in no flying zones. Of course, that filters out the ones that you might like to run around on, the Sky Golem for example, and so it would be good to have the ability to rank things per list.

This could actually be kind of a bitch to do. Currently, a mount can be included in multiple buckets. For example, a water strider is in both the runners and water walkers bucket. We don't show the water walkers bucket in the drop down, but it plays its part when we try to summon the best mount for your circumstances.

No matter how many buckets its in that mounts properties are the same. It has the same name, the same spell ID, the same activation string and the same rank. There's a ton of headaches to deal with if the value of a given property is now dependent on which container its in.

The favor ground mounts checkbox doesn't run into any of those problems because it filters those flyers from being added into the runners bucket.