There have been rumors of new titles, but I'm not sure if anything has been announced. I'm thinking there next step will be to come out with a new Stadium game, maybe on the Wii-U (similar to Pokemon Stadium on the N64, Pokemon Colosseum on the Gamecube and Pokemon Battle Revolution on the Wii). It will most likely feature all Pokemon in 3D, online support and the ability to sync your team from Black and White (and possibly HeartGold/SoulSilver/Diamond/Pearl/Platinum). Another thing they may do, considering their past pattern, will be to remake Ruby and Sapphire for the 3DS. Also, Black and White will eventually get a third title, some people are already calling it "Pokemon Gray". I wouldn't worry too much, though, as there will definitely be more Pokemon to come in the future!