I am deciding between 2 western digital harddrives to put into my unibody macbook 5,1. One is a WD scorpio black 320gb 7200rpm, and the other is a WD scorpio blue 500gb 5400 rpm, the scorpio black is about 10 bucks cheaper so price isnt really an issue. I was just wondering how significant the performance difference is between 5400 and 7200 rpm is for playing games. Will it only affect loading times? or does it also affect frame rates?