Originally scheduled for a September 26 release, Wargaming's World of Warplanes has apparently run into engine trouble, with the developer / publisher pushing the launch back to November 12 in order to "fine-tune the game balance and make sure that every feature is top-notch".
Wargaming posted the news on the game's official website yesterday and other than the above snippet from director of global operations Vlad Belozerov, doesn't provide much else in the way of an explanation for information-hungry fans.
Essentially, Wargaming wants to spend the extra month-and-a-bit polishing the game. Given Warplanes is an MMO, one might have expected a premature release more likely, followed by a series of updates, so kudos to Wargaming for not following this trope of the business.
The announcement goes on to mention that players of the open beta will get to keep their experience points once the big launch switch is flipped, so if you're keen to check out the game and don't mind shooting down bugs along with your airborne opposition, there's no need to wait.
World of Warplanes Release News [World of Warplanes]