Preliminary heads up ahead of 8.1’s release : The folder structure will be changing once 8.1 goes live. Once 8.1 is live and your client is updated , You will have one Data folder shared over your retail , PTR and beta installs.
Your wow folder will look like this -
_retail_ (folder)
Data (folder)
.build.info (file)
World of Warcraft Launcher.exe (program)`
All the existing folders (eg Screenshots , WTF , Errors , Logs , Cache etc etc) will be moved into retail . All executable programs like Wow,exe or BlizzardError.exe and the DLLs will also be moved into retail
Addons should work fine after the migration as the client will now be looking in the new path and the Interface folder should be moved over fine
If you have the PTR installed all it’s stuff will be under a _ptr_ (folder) . I would expect beta to be under _beta_ (folder)
Existing support articles should be updated with this new information