Yes, $499 for unlimited clients. It used to be $499 for 10 clients and $999 for unlimited clients. So for small enterprise that has been using the 10-client edition, the price stays effectively the same and the upgrade from Leopard to Snow Leopard is as expensive as the upgrade from Tiger to Leopard was.According to Macworld, it's $499 for unlimited clients. Ships in September.
http://www.macworld.com/article/141032/2009/06/snowserver.html
Apple is dropping the price for those that do not need the price drop and effectively keeping it the same for those that do. And there is no upgrade pricing at all.