From a reuter's article
Samsung estimates it will cost businesses and consumers to upgrade their computers in order to make them Vista-ready. The number is something of a back-of-the-envelope estimate, based on the idea that there were 37 million PCs sold in the US in the last three years, and that 10% of those will be "upgrade candidates," with each upgrade averaging out to about $100 (we assume the other 90% will be tossed into landfills by owners who want brand-new PCs for Vista). To make sure they get a piece of this booty, Samsung plans to offer bundles that will provide both RAM and video upgrades for about $250. If all of this has you thinking there's some kind of conspiracy between Microsoft and its hardware partners to get you to part with your hard-earned cash every few years, banish that notion! If Microsoft really felt that way, they would have released Vista on time, instead of struggling for years to get it out the door.
Samsung sees $370 million for Vista upgrades - Engadget