nVIDIA’s next release the GTX 580 is up and available at multiple e-tailers before the official launch. Price start from 560USD over at newegg, also there is a limited time promo code for a 10% discount, which brings the price down to “just” 504USD costing about 50 bucks more then the cheapest GTX 480. However here in Europe using geizhals.at prices start from 475EUR (~660USD), but there is much to be considered before jumping the gun on this one, since the cheapest GTX 480 is going for 343 euros at the moment. So it is definitely not the “no brainer” choice over a GTX480 here in the EU.
Update: Cheapest GTX 580 sells at 439 euros in the EU atm.