Unlike rival Microsoft, Apple has consistently been able to get a significant portion of its Mac customers to quickly upgrade to the newest version of OS X, data from a Web measurement company showed.
The last three versions of Apple's desktop operating system have been adopted at a rate almost three times that of the best-performing edition of Windows, 2009's Windows 7.
In the first five months of OS X 10.6, 10.7 and 10.8 availability -- known as Snow Leopard, Lion and Mountain Lion, respectively -- nearly a third of all Mac owners upgraded to the newest edition, according to California-based Internet metrics firm Net Applications.
Five months after its 2009 launch, Snow Leopard powered 32% of all Macs, while Lion and Mountain Lion, which debuted in 2011 and 2012, each accounted for 29% of all Mac machines by the end of their fifth month.
That's in contrast to Microsoft Windows, which has had varied success in the same time span: At the end of its fifth month, Windows 7 accounted for 11% of all Windows PCs, more than twice the 5% share of Vista two years earlier.
Windows 8, which shipped in late October 2012, looks to be on the same usage uptake trajectory as Vista, although that could, of course, change in the upcoming months.
Why Mac owners consistently upgrade OS X is unknown, although it may be related to price: All three of the most recent editions cost less than $30, with the latest, Mountain Lion, priced even lower, at $20.
By comparison, Windows 7's best deal was a short-lived $50-per-license deal during the summer of 2009. An upgrade to Vista's primary consumer-grade edition ran $159 in early 2007.
Only Windows 8, which has not reached its fifth month of availability, has competed with Apple's lower prices for any length of time. Microsoft discounted Windows 8 Pro upgrades to just $40, a deal that began in late October and expires at the end of January 2013.
The difference between OS X's and Windows' uptake paces is more easily explained: If OS X is a dinghy that changes course on a dime, Windows is the behemoth oil tanker that requires miles to take a different heading.
Even with its slightly-increased global usage share -- in November OS X accounted for 7.3% of all desktop and notebook personal computers, up from 6.5% a year earlier -- Apple's operating system is still mostly used by consumers, who can upgrade on a whim.
Not so with Windows. Enterprises -- and they control hundreds of millions of PCs worldwide -- are conservative organizations and historically lethargic in adopting a new OS, a characteristic that inevitably lengthens uptake and turning what for OS X is a trend line that rises sharply into one for Windows that rise ever-so-slowly.
For example, it took Windows 7 more than a year-and-a-half to reach a 30% share of all Windows PCs. OS X 10.7, aka Lion did, that in a third the time.
Net Applications' latest statistics also showed a very close race between Snow Leopard, Lion and Mountain Lion for the OS X usage crown. At the end of November, the trio were virtually tied for share, with Snow Leopard leading at 30% of all Macs, and Lion and Mountain Lion in second and third place, with 29.9% and 29.3%.
Snow Leopard, a keeper for many Mac owners, may be Apple's version of Windows XP, the Microsoft OS that defies obsolescence. Last month, Snow Leopard lost 1.4 percentage points, about the same as the month before. Lion also lost 1.4 points. Mountain Lion picked up the slack from both, as well as a smaller number of defections from 2007's Leopard, to gain 3.5 points.
Net Applications measures operating system usage by tracking unique visitors to approximately 40,000 Web sites. More information about its November stats can be found on the company's website.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His e-mail address is email@example.com.