Apparently, Pokémon Black and White 2 are being postponed for a another year. As we have been told they would be released as the sequel to Pokémon Black and White, they are, according to pictures and articles relating to the topic, supposed to contain event Pokémon we never got to capture in Black and White, like Genesect and Meloetta. Also, they are said to have a combination of Kyruem and either Reshiram or Zekrom as their mascot, and the latter is assigned according to which game version the player has.
However, if things are going like that are, they will have to wait one more year than planned. Perhaps because the producers and game formatters are not fully sure about the plot, or maybe some other mere problem, but nonetheless, it is troubling to gamers across the globe that are anxiously waiting for the new game.
An article concerning the matter can be found here.
(NOTE: There's a reason it's under "BG Community.")