Serebii revealed today the first 3 starters. As usual, fire, water and grass are the types of the starters. Serebii also mentioned that the two main characters of the games are elder than usual, giving us a hint that Pokemon is finally growing up. Apart from that, Serebii promised to have the names soon.
Here are some pictures:
The names are possibly, as posted on PokéBeach, ツタージャ, ポカブ, and ミジュマル, which are Tsutaaja, Pokabu, and Mijumaru.