The way World of Warcraft: The War Within quest rewards work is game-changing for transmog enthusiasts

pcgamer.com:

At the moment, when you complete a quest in World of Warcraft and get rewarded with some gear, only the items your character can use get added to your cosmetic wardrobe, where all your transmog options are stored. This means if you're a leather user, your plate-wearing alts won't get any goodies, aside from maybe a cloak. This tyrannical system is coming to an end in The War Within. 

This system was teased when Blizzard announced Warbands, which unifies your characters by sharing some reputations and item appearances. But now that players are testing The War Within we're actually getting to see how it works. 

In the upcoming expansion, completing quests will unlock every transmog option for your account, regardless of weapon or armour type (cheers, Wowhead). So when you receive some leather boots as a quest reward, you'll also unlock their mail, plate and cloth equivalents. Similarly, your Evoker can collect shield appearances, even though Evokers can't use shields.

The caveat is that only those classes who can use the gear will be able to take advantage of the transmogs, and they can only be applied to the correct armour and weapon types. So you won't be able to make your Evoker look like they're wearing plate armour. 

In addition to this more egalitarian approach to transmogs, the appearance menu has also been tweaked, letting you see the entirety of your collection regardless of what class you're playing. In the live game, you can only see your transmog options for the character you're currently playing, but in The War Within you'll be able to see everything by selecting a class from a dropdown menu. 

I go out of my way to make sure my characters have the best drip, and lately I've been running through a lot of old raids solo to get my Death Knight looking perfect, so this news has filled my shrivelled old heart with joy. 

One question remains, though: will it be retroactive? I've got a lot of old transmogs that I'd love to see expanded to different armour types