I'm not redefining anything, you just don't see 400k being a worthwhile number, and that's fine. Short term retention is a concern of WoW, and all subscription based games.
You're however, ignoring that the low point of Cataclysm was 9.1m subs, and this was with a year lull before Mists, the latest number is 9.6m, and this is during an expansion. They lost some 1.1m subs during that lull, so as we can probably assume prior to the next expansion there will be another big lull it will drop below their previous low. It might pop up a little due to holiday subs, but overall you'll probably see a continual decrease as people do precisely what you do, resub when patches release, play for a bit, unsub, rinse repeat.
I'm not trying to diminish what Blizzard has done, and I'm not really sure why everyone that's posted to discuss this thinks I'm trying to, I'm simply just stating the facts that WoW's best days are behind it. Unfortunately as the fanboys are quick to run to the defense of Blizzard and WoW they're derailing the thread making it seem like I'm saying WoW is over and done, when I'm just trying to say that while WoW's numbers are dropping, they need to generate some buzz to keep their loyal fanbase with their company and this new project, instead of moving on. Otherwise Titan could potentially never live up to the potential it has, and can't ever get out of WoW's shadow, which is a tough task on its own.