Thanks to the Microsoft team, I just got a review unit of the Surface Pro 3 for testing. Look for more updates soon.
While you're waiting for my posts, you may want to head over to the Surface blog, where Manager Markus Weickenmeier has written a lengthy blog post explaining the design choices that went into the Surface Pro 3 pen and digitizer. http://blog.surface.com/2014/05/get-know-surface-pro-3-pen/