I was really interested in a surface but I opted for the Samsung ATIV smart PC Pro and it rocks, Ive done all my art jam stuff on it and its just fantastic to sit on the sofa and relax whilst doodling, The artdock works great on windows 8 aswell even though its not designed for it, so you dont need the keyboard that much. 4gb of ram means zbrush and photoshop run really well. The screen resolution is amazing too
the negatives are,
-tiny 64gb hard drive (but it is ssd, and it has a micro sd slot which I use for everything non system based, 32gb for £13 so its not too bad).
- battery life is 6 hours so it does need charging alot.
- slight delay on first touch with the digitiser pen in zbrush, so a stroke will start ever so slightly late which isnt a big deal once you are used to it, gonna look at zbrushes settings for this though
- Pricey!!! I paid just under a grand for it
I think these hybrid tablet/laptops are fantastic for mucking about on the sofa and relaxing but I would not replace my desktop with one. For me its given me a new found love for personal art as its just so much more accessible.