other details are a bit light, but i have broken down the big news below.
New Characters!
These two are the new starting player characters (no names as yet)
This guy is your new rival, focuses on a Pokémon's Strength (No Name as yet)
This is a new Gym Leader called Homika. She's a Poison Type User.
This is another new Gym Leader. Shizui is a water type user.
And finally we have Akuroma, a Pokémon researcher, researching Pokémon Strength
New Locations!
This is Hiougi City, the new starting location in the game.
Those pictures tease the big change to Unova. nearly half of the region is covered in a glacier. this means that there are several new locations, towns gone, and tunnels. Opelucid City is on the border of this glacier, the road between Castelia City and Nimbasa City is complete. there is now a settlement on route 4. places gone include Driftveil City's lighthouse, construction zone, and cold storage.
New Pokémon?
That picture shows there are some favourites returning to the game. in the original Pokémon Black and White games there were only 156 Unova Pokémon, but now there are 300 available in Pokémon Black and White 2. no new Pokémon were announced, but the inclusion of Eevee is interesting and could tease a new Eevelution.
Source: Bulbanews and