I’m on PC. Forgot WoW on Mac was a thing
Heh, it often feels as if game creators also forget games on a Mac are a thing. 
But yes, does look like it’s pretty wide spread and not limited to any particular OS which hopefully means a fix can be found more quickly.
Been following the thread here as well about it now.
Ozfac, I’m on the same OS version, on a MacBook Pro and was running fine till maintenance this week. Haven’t seen mine beachball yet, but WoW is running incredibly slowly, overheating the Mac, and the lag is making it totally unplayable most times.
Oddly though, the past hour or so was lag free so now I’m wondering if there are separate issues.