It isn't a white PS4: it's a commercial Steam Machines box, or at least a prototype of one. iBuyPower tells us that it's building the box for a 2014 launch, but says it's still early.
iBuyPower tells us that it actually has two models, codenamed Gordon and Freeman, in the works. The two consoles are identical, save for the light bar round the middle -- one model's is clear, while the other's is black when not illuminated. And, while the company wouldn't tell us about the boxes' internals, it did confirm that the hardware will run all Steam titles in 1080p resolution at 60fps.
http://www.engadget.com/2013/11/25/commercial-steambox-prototype/