Apple, onTuesday said it has shipped more than two million copies of Leopard, the Mac OS X upgrade it released on Friday.
"Despite some of the naysayers saying that it was an evolutionary release, not a revolutionary release, this looks like a very successful launch," said Chris Swenson, an analyst at The NPD Group. "In fact, in many respects, Apple is undercounting licences, since it counts a family pack as only one sale."
Family Pack, which sells for US$199, is a five-licence edition that can be used to upgrade multiple machines in the same household. A single-licence version lists for $129.
According to Apple, the two million mark -- which includes sales at its retail stores, resellers and online, as well as copies served under maintenance agreements and those bundled with new Macs -- "far outpaces" the first weekend's sales of Tiger, the previous edition of Mac OS X, which it launched in April 2005.
In a statement, Apple CEO Steve Jobs said: "Early indications are that Leopard will be a huge hit with customers. Leopard's innovative features are getting great reviews and making more people than ever think about switching to the Mac."
Not everyone has given Mac OX 10.5 a passing grade, at least not as an upgrade to earlier editions. Over the weekend, large numbers of users reported problems, including "blue screens of death" that stymied the upgrade's final stages. Some of the blue screening was traced to older versions of APE, an application enhancer used by "haxies," or customizers, to tweak the Macintosh's interface and software.