From this we can gather that the sequel, while a new adventure, still takes place in Unova. However, the starting town, Hiougi City, is at a previously uncharted area south west of the original Unova region. Also, half of the region appears to be completely frozen in ice. The game is also said to take place two years after the first Black and White games. That boy with the wild, frizzy hair is the new rival and the people next to him are the boy and girl player characters. They look very similar to the previous protagonists which might come into play somehow. Black guy in the swimsuit is a new water gym leader while the
girl with the guitar is a new Poison type gym leader. The blonde man is a Pokemon researcher named Akuroma.
In addition to all that, it seems that this time the regional Unova dex will have a whopping 300 Pokemon in it! Psyduck is #26, Riolu is #33, and Metagross is #254. It seems that Mareep and Eevee are also in there.
Changes to the Unova region include:
-Half the region being frozen and areas to the west being revealed. Previously they had been obscured by clouds.
-The Huge blob of ice trapping Unova has two entrances into it, both around Mistralton City.
-Opelucid City is closest to bordering the ice.
-The water around the Entralink area (that Pokeball in the middle of the map) is dried up.
-Challenger's Cave is gone.
-Driftveil City's lighthouse is gone. There also appear to be some craters there.
-Route 4 construction seems to have been completed.
-The construction and Cold Storage areas of Driftveil however...are gone.
-There's a new area at the entrance of Nimbasa City, and another next to the Ferris Wheel.
-One of the original glaciers in Eastern Unova now has a little town in it.