Currently with over 400,000 active players and over 2 Million sold copies Guild Wars 2 is still expanding and attracting more players every day. It is predicted that in a year it might surpass World of Warcraft (WoW) as it has a Pay once play forever policy. It has also been reported that ever since Guild Wars 2 was released the number of World of Warcraft Active players has reduced significantly, and if the new DLC "Mists of Pandaria" can't live up to the players expectation then there is a huge chance that Guild Wars 2 can surpass World of Warcraft - unless Blizzard acts quickly and take action against it. For now it has given the MMO industry a valuable lesson and that is the fact the Subscription based playing is no longer a good option to play games.
Blizzard Entertainment has announced the opening of beta registrations for “World of Warcraft: The War Within,” inviting players to explore new subterranean worlds beneath Azeroth.
Danish from eXputer: "Despite Blizzard's attempt to give a fresh new spin to World of Warcraft, some fans still seem to be stuck in the past."
HG writes: "Blizzard is usually pretty bad at keeping secrets, but the company somehow managed to keep this one under wraps until now. Plunderstorm is a special limited-time event that’s basically World of Warcraft’s take on the Battle Royale genre."
Nope, it won't, but that's not a bad thing. Guild Wars was actually designed to COMPLIMENT WoW, not destroy it. In other words, it was designed for WoW fans to play it and enjoy it but to play WoW, too.
GW was made by former Blizzard employees who worked on WoW and they were huge WoW fans. They actively played WoW even when designing GW. Go back and watch/read some interviews with the guys. It's pretty revealing.