Ars Technica offers an in-depth review of the Modbook 2.0, the third party hack that turns a MacBook Pro into an art tablet with Wacom digitizer. For a quarter of the price, I'd say the Surface Pro compares very favorably.
It's a mystery why Apple has left its dominance over the creative market slip over the last few years. Yes, artists represent a tiny slice of the marketplace, but they were the segment that kept the company in business during its darkest post-Steve Jobs years. Just imagine if Apple were to release an Air with iPad-like touchscreen...