From
Samsung NX concept features compact footprint, APS-C sensor:
"Lens mount uncertainties
Although it wasn't spelled out in today's announcement, product shots and technical discussions suggest that the NX series will retain interchangeable lenses as well. Given the lack of concrete information on this front, it's also not clear what lens mount Samsung might be planning to use.
What is known is that Samsung has a long history of building DSLRs around Pentax's K mount. With lots of tiny "pancake" primes in Pentax's DA Limited stable that would fit nicely with the equally compact NX, Pentax is the obvious frontrunner in our minds at this point. Assuming this pans out as expected, it would be a boon for Pentax shooters, providing a compact body option even smaller than the current Pentax K2000."
So obviously they kept them in the dark by not telling anything about the optics, not even for sure that it is interchangeable, nor the mount, nor who will make the optics. The Pentax-line is just speculation by digitalcamerareview.
I can't see how they could make k-mount pancakes work without an adapter, and then they just loose again the gained 40% depth they got from dropping the mirrorbox.
Have you notived how totally anonymous the lens in their press-release pictures are? Not single mark on the lens, which makes it hard to guess anything.