Rumor is that the NEX FF will not be much larger than a current NEX-7. The Sony RX1 is also a good example of how small you can make a fullframe mirroless camera.
E-glass has been pretty crappy so far. They're now launching a few good ones. I'm excited about the alpha mirrorless opportunities though. Maybe we'll finally be able to have a SLR-like body that's agnostic to mount.