So I have a 15" 1.67GHz Rev. D PB with (currently) 1 GB of RAM (2x512 MB). My question is how much improvement will I see if I upped this to 2.0 GB? Prices are getting lower all the time, and I'd like to feel a <little> closer to the MBPs (though I know that's not likely). Mainly I use my PB for iPhoto, iMovie, GoLive, websurfing (on MR of course), some Keynote presentations, and a little Pages/Word work. Nothing too intense.