Will this ram upgrade 1 gig to 4 gigs make a huge difference in gameplay?

I have a Toshiba Sattelite computer, L350-ST2121, with a Intel GMA 3100, I currently have 1 gig of ram and windows vista home basic. I play world of warcraft, and I was wondering if upgrading from 1 gig to 4 gigs of ram will significantly improve my fps and other aspects of the game. My processor is also a duel core 1.86 ghz. Essentialy im asking if the 60 bucks im gonna spend is worth it