Whenever a new big MMO was announced many people would start to talk about how it was going to kill WoW, how it would come in and take away all the subscribers. I think by now most people have realized that the strengths of WoW, those which allowed it to grow so large as an MMO, were the exact reasons nobody could ever steal away massive quantities of the subscription base. WoW has an entire culture built up around it, so many people invested in it, that attempting to just supplant them all at once and shovel them into a new culture, a new MMO that they have nothing invested in, is an impossibility. There is no doubt that games have chipped away at some previous subscribers of WoW, but most often the new MMO turns out to be highly niche based rather than a new all encompassing world. Even with all these new MMO games coming into the market, Blizzard loves to point out that their subscription base continues to grow.

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