I have just bought an iBook 12" running at 1.33 with a built in 512 Ram. at the point of sale, the reseller told me that the gain would be very significant if I were to add another 512 Ram. Since I am a newbie, I did not take up the offer. I wonder if by adding another 512, how significant is the gain. Could any long term user advise? Any comment is welcome. Thanks.