Well your loading times would probably increase, and you'd be able to gloat and brag about having 1GB...so in my opinion, order it, slap that baby in, and go on with life...
You're probably going to get a bunch of other replies saying its not worth it unless you use memory intensive programs....Or they'll tell you to use the search feature(I hate when they reply like that).
I personally say its worth it, loading times will be improved alot, especially if you use some of the registry tweaks available...