Im sorry that i dont believe that, Amazon said a couple of weeks ago that CIV V will be out for linux on 22nd of october ...
(dont get me wrong i really would love to believe and it is still possible since blizzard said they will publish a game this year on linux
but still i want to see it happen first )
Thankfully WoW works extremely well via WINE. I've been running it using CrossOver for years now, with nary an issue. The few minor issues I did encounter, the CrossOver tech support folks were fantastic in getting them resolved fast.
But yes, a native client would be most welcome. Between Steam and Wow, that covers a huge audience, and would hopefully encourage other A-list developers to produce Linux builds.