Some new info from leaked scans of the new issue of CoroCoro (credit goes to Bulbapedia):
Black City is exclusive to Pokémon Black, while White Forest is exclusive to Pokémon White. Cities will vary in appearance between the two versions
Professor Araragi apparently gives the player the Isshu starter Pokémon to begin their Pokémon journey. She asks the player to share them with their childhood friends, Bel and Cheren. Bel is described as a spontaneous person who goes on Pokémon journey against the wishes of her father. She is known to be unreliable at times. Cheren is described as being intelligent and trustworthy, and he wishes to become the Isshu champion. He tends to give advice to the player on their journey.
Triple battles are set up so that the middle Pokémon is able to target all 3 Pokémon, while the ones on the sides can only target their opposite sides. Pokémon positions are able to be switched on the bottom screen with a button. It is said that if the middle Pokémon attacks, there will be some kind of attack boost.
There is a new ability called Telepathy, which prevents damage to teammates (with the ability) when an attack that would normally hit them is used.
There is an unnamed attack similar in function to Telepathy which prevents damage to both teammates.
The routes seem to have been reset. The game begins on Route 1 (This I strongly hate, BTW)
N (a character revealed a few weeks ago), is seen as an antagonist. He regularly challenges the player in order to confirm his ideas of justice. He calls Pokémon "friends", but one of the screen shots shows him saying that he wants to split humans and Pokémon and divide them to create a black and white world. He has the unique idea to set Pokémon free from people, and looks for the power to bring his idea to reality.
7 new Pokemon revealed:
*Rankurusu (will be exclusive to one of the versions), the Amplification Pokémon. It is a psychic type and has the abilities Dust-Proof or Magic Guard.
*Gochiruzeru (will be exclusive to one of the versions), the Celestial Bod Pokémon. It is a psychic type and has the ability Frisk and will know a move called Magic Room.
*Kibago, the Tusk Pokémon. It is a dragon type and has the abilities Rivalry or Mold Breaker and knows the move Double Chop (based on its look, I would guess it is this gens version of Larvitar).
*Koromori, the Bat Pokémon. It is a psychic/flying type and has the abilities Unaware or Klutz and knows the move Heart Stamp.
*Minezumi, the Lookout Pokémon. It is a normal type and has the abilities Run Away or Keen Eye and knows the move You're First.
*Wargle, the Valor Pokémon. It is a normal/flying type and has the abilities Keen Eye or Encourage and knows the move Free Fall.
*Musharna, the Trance Pokémon and the evolved form of Munna. It is a psychi type and has the abilities Forewarn or Synchronize.
Both Munna and Musharna give off Dream Smoke, which is described to hold the dreams of Pokémon. By obtaining Dream Smoke, the player is able to use Game Sync to upload their Black and White save file to the Internet.
The High Link is a building in Isshu where the player is able to connect with other players. With this, multiple players may play Black and White together.
The DS's infrared is now being utilized for quick battles (up to 4 players) and trades from the player's party or PC Box. Along with this, friend codes can be sent this way.
A new feature called Passing By (which is a part of the C gear) allows players to seamlessly and instantaneously connect with nearby players. Professor Araragi's friend Makomo gives the player the C Gear after the player does something for her.
Another feature called Feeling Check checks the compatibility between players. A game is shown where players must keep the same rhythm.
Live Caster is a feature where players are able to video chat which includes a pen and stamp to allow editing. This feature is also used by in-game characters from time to time.
Pokémon Global Link is the service that allows the uploading of Black and White save files and has 2 different modes. One mode allows the player's Pokémon to play in a dream, while the other allows the player to battle online. Access to the Global Link is gained by obtaining Musharna, the evolution of Munna.
There is a 'Dream World' where Pokémon have their own rooms to play in, and are able to play mini-games with other Pokémon. If a Pokémon is befriended in the dream world, it is able to be taken back to the player's game. Hence, this allows Pokémon not native to the Isshu region to be obtained. To send a Pokémon (the Pokémon must be placed in in the PC box) to the world of dreams, the Game Sync feature (part of the C Gear) is used.