Update: Sadly, the teaser was revealed to be an iOS RPG titled School Girl Strikers. It's sad both because it's an iOS game rather than a full RPG console release and also because it's unlikely to ever be ported to North America due to the nature of the content and the fact that western audiences tend to have little interest in these sorts of games. Ah well. Square Enix also released a "Sound & Audio" trailer (in Japanese) that sets the mood for the RPG.
Source: School Girl Strikers
Thanks to Rabla for the tip!
Recent quotes coming out of Square Enix may imply the company is reconsidering how they approach RPG development, largely due to how well Bravely Default did worldwide. Perhaps Square Enix executives have just been preparing the public for announcements like what they've put up today. A teaser site has appeared at the URL "http://team043.jp/" for an RPG described as Ranobe style, or a light novel.
Square Enix teasing a light novel RPG? Perhaps there's some sort of April Fool's Joke going on and it has been lost in translation, or maybe Square Enix really is planning on experimenting with the RPG genre going forward. It's hard to see them going so far as to make a big, world-wide light novel RPG right off the bat though. I'm thinking that "team043" and its associated project is, it'll be a small-scale and perhaps mobile game. Still, it's a start.
Stay tuned for more information on team043 in the weeks or months ahead. The site, as far as I can tell, doesn't reference when any further information will be revealed, but these sorts of things don't tend to linger very long. I'd say news will be coming soon.