What you're seeing here in this rather confusing set of images is a leaked product from Sony, a brand new lens adapter with a brand new twist - a mirror! This is the LA-EA2, a lens adapter that allows you to put Sony's Alpha SLR lenses onto all of its smaller NEX cameras. While this sort of situation generally just has a few jimmyrigged bits making the lens not quite as awesome fitted onto the camera that's not normally meant to have the lens, this new piece of equipment has a translucent mirror inside to collect a tiny bit of light from the image as it travels into the camera, this light then sent to a phase-detection autofocus sensor in the base.
What this will get you is a teeny tiny mirrorless camera with a brand new mirror, SLR-speed focussing, and an overall sweet result. Contrast detection in AF used in cameras that normally have no mirror is quite slow at the moment, especially when you're considering you're using lenses made to rock and roll. Now you've got a small gun messing with the big guns, if you know what I mean. Does this mean the device you're rolling with is still a mirrorless camera? You be the judge of that - we're calling it an advanced frankenstein.
This type of new mirror is called a "pellicle mirror", and isn't actually all that new when you consider it's been being used for more than 40 years by the Pellix 45 made by Canon in 1965. This camera was the first to use such a mirror and it's been used sparsely since - of course you can see the mirror type in action again in the Sony A55 and A33 DSLRs of 2010, too. Why on earth this solution hadn't been used in lens adapters up until now - we cannot say. It's sort of like pop art - it seems so obvious, but the first person to do it gets credit!