I just purchased Snow Leopard on the online Apple Store. The emailed acknowledgment states that it will be delivered Friday, August 28th. Quibbling with the terminology being used in some places, I would say that Snow Leopard is on sale NOW and will be delivered Friday.
Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5
