That number is 80% higher than sales of the previous operating system, Snow Leopard, during a similar stretch in 2009, Cook added during the early minutes of a presentation at the company's Cupertino, Calif. campus to .

Cook also took a shot at rival Microsoft and its Windows 7 operating system, saying that Lion was powering 10% of all Macs within two weeks of release, compared to Windows 7's taking 20 weeks to match that same level of penetration.

What Cook omitted was Microsoft's much larger share of the operating system market, and thus the need for Windows 7 to sell a much larger quantity of copies to reach a 10% share of all Windows machines.

In September, Microsoft boasted that it had sold more than 450 million copies of Windows 7 since that edition's 2009 debut.

According to Web metrics company Net Applications, Lion was running about 22% of all Macs that went online last month, while its immediate predecessor, Snow Leopard, accounted for 55% of Macs and 2007's Leopard powered about 18%.