News and rumor site Fudzilla is reporting that Nvidia's GeForce GTX 580 videocard is going to launch in November, probably before AMD's Cayman architecture. If true, look for the GTX 580 to show up around the middle of November.
Of course none of this is confirmed, but according to reports, Nvidia will likely target a $500 price point for its upcoming GPU, depending on how AMD's Cayman cards perform and how AMD chooses to price them.
In related news, a forum member on Chinese-language site PCInLife.com posted a couple of pics of what he claims is the reference design for Nvidia's GTX 580 part. You can check them out here.