Help me find my next laptop?

I currently use a mid-2010 13inch Macbook Pro, and am looking to upgrade around Christmas time. I'm more interested in portability and battery life, than having the best possible specs. My budget is around $2000 give or take. Right now I'm looking at either a Windows 8 Pro tablet like the Surface Pro (mainly for the active digitizer (taking notes via OneNote is amazing!)). If I got a Windows 8 Pro tablet, I would save about $1000, which I could put towards building myself a gaming PC. I've also been considering a Macbook Air (since the new retina 13 inch MBP seems pointless), or just full out get the 15 inch Retina MBP, which would easily run my games (Guild Wars 2 mainly), and still have the great battery life and portability.

Does anyone have any other suggestions or ideas?