A new Eeveelution is pretty obvious at this point, a great way to kick off the Gen 6 hype. The typing could actually be a whole new type like Smalllady mentioned earlier, I see no reason why not if Gamefreak want to get creative on a new platform. Then again, could also be the last final former special type: Dragon.
Either way, cannot wait to see it. If anything this should be the final nail in the coffin of the Gen 6 not coming in 2013 people, its definitely coming.