MacRumors has some info pointing to a 20- and 24-inch iMacs with NVIDIA graphics. While anyone with a printer could make these exciting marketing materials you see before you, another Swedish reseller had a weird page describing an unusual configuration as well, so there’s some hope that the update will come sooner or later.
Don’t let this dissuade you, dear iMac owner to be. As I always say with Apple products: if you need the product, buy it. The next upgrade will be incremental at best. Don’t base your decisions on blurry cameraphone shots of paper.