Blizzard believes World of Warcraft can happily co-exist with the unannounced "next-generation MMO" that it is currently developing.
Speaking at Blizzcon last weekend, president Mike Morhaime told GameTrailers, "We are working on a second MMO. We're thinking of it as sort of a next-generation MMO. It's not a sequel to World of Warcraft - we want to do something a bit different.
"We're not trying to replace World of Warcraft. We think that World of Warcraft can continue co-existing with our new MMO and some people might prefer the new one, some people might still prefer to play World of Warcraft."
"But I think after building World of Warcraft the first time, we're so much smarter now," he added. "We have a lot of expertise that we didn't have before. And I think we also want to sort of... every massively multiplayer game doesn't have to be similar to the ones that exist today.
"We think you can go in different directions and still have a great massively multiplayer experience and we want to sort of experiment with what that might look like."
Don't expect to hear any more about Blizzard's next behemoth for some time. According to VG247, the earliest we'll see a reveal is 2012.