My 5 guesses, in order of most likely to me;
1: Pokemon+new move (maybe Extreme speed Genesect)
2: New Wii/Wii U game
3: Another Bonsly/Mime jr./Munchlax thing
4: RSE spin-off
5: Manga exclusive for N (or something like that)
And I know that balbapedia(?) had a news thing talking about a new stadium wii game being made right before black/white came out (I'll go see if I can go find a link for that).
Also, if they give new a ability to a Pokemon that is not open/hidden in the current games they would have to upgrade the black/black2/white/white2 games, which is not likely (of course they could game lock it like the spiky-ear Pichu or the griseous orb if it's in a new game).
I told you not to do that!
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