This isn't confirmed but there has been talk of Sony coming out with a Full Frame camera.
http://www.sonyalpharumors.com/amazi...-new-a99-pics/
A few days ago Steve Huff was able to look at all the new Sony stuff that will be showcased at Photokina and though he wasn't allowed to talk about it, he did mention there was something great and unexpected coming from Sony. This leads me to believe the RX1 is what he saw.
The big questions for me are price, whether it's a fixed lens or interchangeable lens system (it appears fixed) and whether or not it has a viewfinder or not (I'm guessing they would have to have the option to add one at the very least).
There's some very interesting cameras coming from Sony lately.