In a word, no. Adding RAM makes the computer run smoother when doing heavy tasks or when running several applications at the same time. Some people seem to be under the impression that have a ton of RAM is equivalent to having a faster processor. The less your computer has to access from the hard drive, the quicker the application will respond. If you're simply running Safari, iTunes, iChat, Microsoft Office and iPhoto, I doubt you'd see much difference at all. Unless you have a habbit of running lots of applications at the same time as well as some hefty Dashboard widgets, you're probably going to be fine with 1Gb.