I would love to see the whole Grass/Dark Fire/Psychic Water/Fighting thing happen but i highly doubt it.
Seeing the animals they're based off of and their names, it's safe to assume the typings:
Fire Ground - Fennekin [Fennec foxes are desert foxes]
Water Flying - Froakie [White fluff suggests clouds, and there are flying frogs]
Grass Steel - Chespin [Name: Chestnut + Pin, kinda self-explanatory]