Even if we were talking accounts and not characters (which I think we are) the fact of the matter is that they consistently have 11.5 million subscribers. This means that something like 36 million people have given the game a try. Seems like a very good level of player retention to me, especially since the annual subscriptions far surpass the money needed to maintain the game. Also, they haven't had an expansion in almost a year and a half, a lot of people have probably gotten bored and may be coming back when Cataclysm launches (while new players will be sure to try it out, too). If, after their next expansion, the regular subscribers begin dwindling on a constant basis THEN we can say that WoW has hit a tipping point. Right now what we're looking at is a large boost in player interest (and added revenues) due out within a year or so.
You do not have the right to never be offended.
Essay Pro