I'm tired of lugging my 17" Pro around so I've gone for the new MB with 4Gb RAM. At work I'll be plugging it into my 24" ACD and at home I'll just be surfing so screen size I can live with. SketchUp runs fine on the Air so it should fly on any of the new MacBooks and tests show that the base MB is close to the MBPro in performance. For me this is the ideal setup. I truly portable powerhouse computer and a nice 24" monitor at work.