There's probably somewhere around a billion PC gamers out there,sure that includes people that play solitaire once a month and is spread over an incredibly diverse range of games and delivery methods, but the point still stands, the majority of people that have a computer do some gaming gaming in some shape or form at least periodically. A massive chunk of those aren't ever going to be savvy enough or want to lay down extra cash on discrete hardware dedicated to gaming but if they have it already, what's to say a lot of them won't use it?
The way the market works atm most people with a PC are locked out from any game released in the last 3/4 years if it isn't a PopCap title. This changes all that, as AMD's low end consumer should have enough GPU grunt to play any PC game in some fashion at least, quite possibly more often than not at more than satisfying settings for most, especially since AMD plans to refresh the GPU packaged each and every year. That opens up PC games (and GPGPU applications) to a much bigger market which can surely only be a good thing?
Countless have tried to run WOW on Intel integrated graphics for example but its such a terrible experience I doubt many persist, if such customers instead buy an AMD chip in the future they get to play WOW but not lose any other tangible real world functionality at all. I spend a fair amount of time offering PC hardware advice to a very (primarily console focused) popular gaming forum, and yes, a lot of people on low end notebooks/desktops do ask if they're capable of playing modern games, it might just be for the latest Valve release, WOW a Train Sim or C & C but the only constant is that anyone with a current integrated solution is in for a shitty experience if they don't upgrade their graphics hardware, and since many use laptops or awkward prebuilt PCs this is often not an option for them, so they're totally SOL.