Microsoft's Surface has now launced but as that is the RT version (touch only)
I've been looking around the internet for a pen input device,
so when I come across any new info or vids then I'll give them a mention here.

...Compare the Wacom active digitizer pen of the new Samsung Smart PC 500T to the
N-Trig active digitizer pen of the Sony VAIO Duo 11 with a quick brush test with Autodesk Sketchbook Pro 6.