According to the recently-revealed statistics by the research firm NPD Group, the first two weeks' online and store sales of Apple's new operating Snow Leopard, Mac OS X 10.6, by far surpassed the sales of Apple previous two operating systems - Leopard and Tiger.

Going by the data forwarded by NPD, the two-week sales figures of the Snow Leopard, released August 28, marked a twofold increase over the sales of its immediate predecessor, the 2007-launched Leopard; and a four times increase over sales figures of the 2005-launched Tiger.

The NPD Group numbers also revealed that between the first and second week, the sales of the new OS dropped nearly 25 percent; as against the 60 percent drop in sales that both Leopard and Tiger witnessed in their respective second weeks of release.

Noting the "outstanding consumer response" to the Snow Leopard, Stephen Baker, the NPD Group's VP of industry analysis, said that Apple's "aggressive pricing policies" helped Snow Leopard outsell its predecessors. Apple has priced the single license Snow Leopard OS at $29, and the five-license family-pack at $49 - which is $100 less than the corresponding Leopard packages.

Baker added: "Even though some considered Snow Leopard to be less feature-focused than the releases of Leopard or Tiger, the ease of upgrading to Snow Leopard and the affordable pricing made it a win-win for Apple computer owners, helping to push sales to record numbers."