I'm considering upgrading my 2008 Unibody 15" MBP. I was wondering if the new 13" 2013 MacBook Air would be a large jump in performance? I play light video games occasionally, and use Adobe Photoshop & Illustrator frequently too. Personally, I think this is a good time to upgrade, there are no marks or imperfections on the MacBook, and I have also fitted a 500GB 'hybrid' drive, similar to the fusion drives of the newest iMacs. One concern is the lack of dedicated graphics on the Air, compared to the 9600GT. What do you think I could get for it second-hand in the UK? Thanks for any tips.