I know that the Macbook has integrated graphics so I was wondering is there a major performance change (with the current model +4 gigs or RAM) if you have extended desktop with a second monitor?
I hook my MacBook up to my external monitor quite frequently and I've not noticed a performance hit. Although I do find the image quality is not as good as it is when I plug the screen into my main PC running OSX. I'm guessing it is because I have to use the Mini DVI to VGA converter.