(would've posted in news if I could *cough*)
Ash is revoked as the main character to make room for Red and Green, the two main rivals from the original games. It will follow Red's journey through Kanto as a new pokemon trainer with his starter pokemon, Charmander. It is unknown if the show will include the 2nd generation of games, if he has travelling companions, or even if it is a TV series or just a special.
It airs October 2nd.
I think it looks cool. I wonder if it'll overlap some storylines from the manga, since the manga was based off the games.