Difference being, faction changing comes at a price, making it a quest or automatic dosen't affect how much money they get out of it.

Not only that, but as they have said "Defecting" is different from what Blizzard are implementing, you don't keep your character and change sides, you get a new character of that faction and then a "Similar as possible" stat and gear copy.

It would be stupid and imo very weird (not impossible, but in game terms weird) to have tauren on the alliance, etc.

I have a feeling that the next expansion will be announced during Blizzcon as being a mid-2010 release. WoW has been around long enough and has an established enough playerbase that Blizzard will be looking to release things like SCII and D3 for Christmas.

"Like many game designers for team-based or multiplayer games, Blizzard believes (correctly) that silhouette is an important factor in telling friend from foe."

See, I don't really buy this. Yes, it's easy to tell a gnome from a tauren silhouette, but can any of you, at a glance, tell a female orc from a night elf from a blood elf from a human from an undead from a troll at a distance? In full armor? While running?

Personally, I look for the red name in PvP, but that may just be me.

That said, I might be okay with the idea of defectors--but they should never be able to raise their reputation with any of the alliance factions above neutral. You've deserted your home faction to join the other side-- well, great! But we'll never really trust you.

I can, actually. It's a matter of posture and general shape. With the exception of Blood Elves, most Horde races have a generally hunched posture. And while this doesn't stand for female orcs and trolls, the female orcs have builds similar to male humans (but curvy), while the trolls are tall and gangly. It doesn't take much to identify them, really.

That said, the whole "quest chain for faction change" appears to have been an idea that was kicking around since the First Beta (languages count as skills, after all), but was nixed for a variety of reasons. If they turned it down from the beginning, and are still making you change your race now, I doubt they will ever implement it in the future.