I must admit I'm very confused right now about all the different hardware standards for styluses. There's the USI, Wacom EMR, Wacom AES, the newer G13 series, and something about "Dual Protocol" pens soon to be released. Can someone sort all this out for me? One thing I'm trying to understand is: if I were to, say, buy a Surface Pro 4 today, and Wacom releases a "Dual Protocol" stylus with tilt support in a few months, will it work with the Surface (including said tilt support)? Will we finally be free to buy tablet PC hardware without it being locked in to a specific stylus variety?