"Who Moved My Cheese," as he says, is one of those corporate management books that's a little trite for anyone but executives to actually read seriously -- it's got a fable about two mice who find a chunk of cheese, and then have to deal with what happens when change hits them and that cheese runs out. And BBB then takes that into the act of playing WoW: right now, this game is giving us plenty of cheese, and when the expansion drops, things will be even better. But at the same time, there's no reason to stick with the game if it isn't giving you what you want, and as we've said before, if you're not interested in the game, feel free to go find something else.
BBB's post is a great read, and it's refreshing to hear an honest take on what it might mean to finally end a career in WoW (not that BBB is doing that yet). There's a lot of stuff left to do in Azeroth (and there'll be more to do in Northrend). But at the same time, there's nothing wrong with making your own path and going off to find yourself some fresh cheese.