$850 will get you a monstrous gaming rig. A GTX 770 (Logical Increments' recommendation at that budget) will run anything at 1080p/60FPS, usually at maximum settings (which is worlds better than...
I feel like the popularity of each Surface Pro has been significantly greater than the one before it. Perhaps the difference was great enough that MS just still hasn't sold out of SP1s.
Maybe MS will rewrite it in C++/DirectX to get it on the Windows Store. That would certainly be an improvement performance-wise.
iOS and Windows Phone just got shiny new releases. This new version just hasn't rolled out for Android yet.
This isn't just for Home and Personal. I have 365 University, and I got my 1TB today as well.