Hi guys. I'm a complete newbie when it comes to computer hardware and I was wondering if I'll see a noticeable difference if I upgrade the ram for my new MacBook (white unibody) from 2GB to 4GB. I think it will cost around $90 for this upgrade and I don't want to do it if it's not really necessary. My main work on this comp is for iPhone dev. and some video/photo editing. Thanks!