Like I said before, WoW's not going to die until Blizzard decides to pull the plug on it. GW2 and SWTOR won't kill it off by taking a large chunk of Blizzard's subscribers. They will take a fair amount, maybe even a few million, but that'll still leave Blizzard with over 9M subscribers. The new IP Blizzard's developing won't kill WoW immediately; Blizzard will eventually phase it out in favor of the new IP to be their new cash cow.
@OrangeKun- In regards about the devs, if you want to get technical, Boo-Yeah meant to say the remaining original WoW devs were all moved to the new IP. Layoffs and resignations happens, that's business.