Starlin, ty for the update. It's appreciated. :)

"but who can blame them for being slow to change them when they get the horrible backlash nearly every time they DO change a model? (New Tree of Life, anyone? That's just the most recent example.)"

I'll blame them.

The new ToL didn't get "backlash" so much as it got some funny reviews... personally it's not that bad, and depends on how it moves. I think it will turn out fine. And how about all the cat and bear updates? Pretty much all praise, no backlash. Didn't they also update models for Varian Wrynn and Jaina Proudemoore? I thought those ended up being positive changes overall. And the old ToL was virutally universally panned. Yes, I know a lot of druids love their beloved tree form, and I feel for them, but even the most ardent tree-lover would admit that it looks like a piece of dead broccoli.

To this point:

"That, and a model change means they have to re-rig how all the armor, mounts, and animations work for each race/sex."

I'm not a 3d modeler, but my very rudimentary understanding is that if they keep the same basic geometry, it shouldn't be overly taxing. (The discussion in the queue on how robes over-write tabards helped; it was something like each piece of armor has it's own "graphical" slot, so if that's the case, just plugging textures into those slots shouldn't be much more difficult than creating new pieces of armor.)

To your other points, you are basically quoting how a lot of people QQ on forums. Forums are where people do nothing but bitch generally. I think the greater wow community is a-okay with a Mastiff; just because a few mouth-breathers want a rabid-looking Rottweiler doesn't mean that most of us think like that.