UPDATE: Leopard is now #1 in software top sellers while Leopard Family Pack [1] appears on the top ten as well in the 4th position.

Amazon has made available Apple's Mac OS X Leopard for pre-order [2] on its online store.

Apple's major operating system upgrade is listed at $129 and Amazon guarantees that in case they drop the price until it ships to you, they will update your order so that ou can benefit from the new pricing.

The product is already ranked #3 in the Software category bestsellers [3] with respectively Microsoft Office Home and Student 2007 [4] and Microsoft Office Student and Teacher Edition 2004 Macintosh [5] preceding it.

Amazon has historically been very agressive in terms of pricing and availability of Apple software and hardware.

Leopard is scheduled to ship on October 2007 and pre-orders [6] are currently only available to U.S. customers.