[UPDATE: As of 01/14/2008, Blizzard has announced that this creature can no longer be tamed. This reverses their previous comments on the matter.]
According to a post by Issuntril, a Blizzard Poster, on the European In-Game Customer Support forum, the Ghost Wolf is here to stay:
While this feature of the Grimtotem Spirit Guide wasn’t exactly intended, it was agreed by the development team that this is a fun use of in-game mechanics, and we therefore have no plans to address this issue – it will still be possible in future for everyone who wishes to tame this NPC to do so. :)
I hope this alleviates your concerns!
I haven’t seen anything on the US forums yet, but I don’t believe that it’s even feasible to leave this is Europe and fix it in the US. So yes, that alleviates many of my concerns! Now I just have to find time today to get the wolf added to Petopia.
My thanks to the legions of people who immediately let me know about this, here and in e-mail.