Originally Posted by Solstice

I think there's some confusion about this. The ToS states clearly that modifying game files is not allowed. So for example, if I were to go into my common.mpq file, alter some of the models around and use a 3rd party program to start up WoW, yes that would be against the ToS and I would most likely get a ban sooner or later. WoW has an inbuilt program to protect against this, I forget the name but it basically scans your game files when you log in to check if anything has been altered.

However, to change the cat and bear models you don't have to edit any game files. You simply name the models you want to use the same names as the cat/bear files, pack them into an mpq file and pop it into your data folder. In that sense, it's no different from using any other interface enhancing mod. If Blizzard didn't wish to allow this it would be extremely easy for them to remove this functionality.

Besides this, I can recall seeing 2 separate screenshots, one from a GM in-game telling someone in no uncertain terms that it was fine to change model skins so long as it didn't effect how other players view them, and another in the form of an email from Blizzard technical support stating exactly the same thing.

I agree that it IS a gray area, what they want to be sure to prevent is anything that could be viewed as cheating, for example changing herb nodes or pvp targets to bright red arrows. So long as you don't cross this line I'm convinced that they're perfectly ok with it. If you have some official information stating otherwise I'd be interested to see it, preferably before I get banned ;p