The Nintendo Direct presentation at the E3 games conference has just confirmed there will be a new elementary Pokemon type introduced in Pokemon X&Y - the Fairy type! This has been rumoured for a long while now, ever since Sylveon was revealed.
Sylveon is Fairy type, but also Jigglypuff, Gardevoir and Marill have been confirmed to now be part-Fairy type (Normal/Fairy, Psychic/Fairy and Water/Fairy respectively). More Fairy Pokemon may be confirmed later.
Two new Pokemon have been revealed - Vivillon, based on a butterfly, and Noivern, based on a dragon (or more precisely a wyvern
). Three new moves are in the trailer - one called Boomburst
as used by Noivern, a Fairy-type move called Moonblast
as used by Sylveon, and another Fairy-type move called Fairy Wind
as used by Gardevoir.

Noivern (left) and Vivillon (right) official artwork
The release date is also confirmed to be October 12th, 2013 worldwide. Here is the new official Pokemon X&Y gameplay trailer:
Our Pokemon X&Y page will be updated shortly with these and more details!