OS X Mavericks, the Mac operating system Apple offered Tuesday as a free upgrade, could end up on more than 90% of Macs, according to statistics from a Web analytics company.
Net Applications' latest data showed that 93% of current Macs run last year's Mountain Lion, 2011's Lion or 2009's Snow Leopard, all eligible for the free upgrade to Mavericks.
The California metrics firm measures operating system user share by tallying unique visitors to the tens of thousands of websites run by its customers.
But while some analysts have seen the free deal as a poke at rival Microsoft -- which has charged fees for its Windows upgrades, if not for interim updates like the recent Windows 8.1 -- Apple may have had other reasons in mind.
By pushing Mavericks, Apple can hope that a larger percentage of its customer base will upgrade, reducing OS fragmentation. As in iOS, whose users typically upgrade in droves to make the newest the default in weeks, a Mavericks strategy will give OS X developers a bigger target: The free upgrade means that developers can assume most Macs will be running Mavericks, and write for that edition to take advantage of new APIs (application programming interfaces) and features unique to OS X 10.9.
And if Mavericks is the standard, it also means developers will be more likely to abandon support for earlier editions. If they don't have to provide backwards compatibility to Mountain Lion and its predecessors, the thinking goes, they can put their energies and resources behind new work, not spend it on support for older software.
As of Sept. 30, 49% of the Macs that went online worldwide were running OS X Mountain Lion. Lion and Snow Leopard were tied for second place, each with a user share of 22%.
The rise and fall of each new edition of the Mac's operating system has been predictable, with both Lion and Mountain Lion reaching a 49% penetration by the time they were supplanted. Snow Leopard, which had two years at the top of the pile -- versus the one year for Lion and Mountain Lion after Apple accelerated its release pace -- reached 67% before ceding share to Lion.
That cyclical pattern has been upended by Apple's decision to make Mavericks a free upgrade, and if history is any indication, the move will quickly draw down not only Mountain Lion's share but also significantly reduce those of both Lion and Snow Leopard.
However, some will resist upgrading to Mavericks, take a pass on the deal and stick with what they've got.
From all accounts, the hardest edition to eliminate will be Snow Leopard, Apple's Windows XP-esque OS that has been more resistant to suppression than the norm.
Many customers will stick with Snow Leopard because it was the last able to run applications designed for the Apple/IBM/Motorola-designed PowerPC processor.
About 93% of all Macs that went online in September are eligible for the free OS X Mavericks upgrade, but don't be surprised if a chunk of the 22% running Snow Leopard take a pass. (Data: Net Applications.)
Apple ditched the PowerPC processor in early 2006 when it shifted to the industry-standard Intel. Snow Leopard is the newest OS X that can use Rosetta, the translation utility that allows PowerPC software to run on Intel Macs. A year ago, when Computerworld published a story about Snow Leopard's resistance to retirement, users who planned to stick with the edition because of the PowerPC issue came out of the woodwork.
"I would love to have some of the new enhancements in Mountain Lion, but I have lots of software that I still use, and want to continue to use, that is PowerPC only," reader James Frederick said in a November 2012 email. "That will all die if I 'upgrade.' Because of this, I will not do so."
Mavericks' zero price may also get Apple out of a different jam.
Because of Snow Leopard users' stubbornness, as well as its faster release cadence, Apple has supported OS X 10.6 -- Snow Leopard's numerical designation -- much longer than earlier editions. If a significant number of Snow Leopard users do upgrade to Mavericks, Apple could pull the security update plug.
Historically, Apple has patched only the OS X editions designated as "n" and "n-1" -- where "n" is the newest available -- and discarded support for "n-2" either before the launch of "n" or immediately after. Under that scheme, Apple should have stopped serving security updates to Snow Leopard ("n-2") in mid-2012, when Mountain Lion (designated "n") debuted.
Instead, the company continued to patch Snow Leopard; the latest security update shipped six weeks ago.
Apple may have now called it quits on Snow Leopard security updates: Although it cited 53 security vulnerabilities patched in Mavericks, it has not issued a corresponding update for Snow Leopard (or for Lion or Mountain Lion).
It's conceivable that Apple will simply stop patching all versions of OS X prior to Mavericks, dispensing with its unwritten "n" and "n-1" support policy. If pressed, it could justify that decision by pointing to Mavericks and urge customers to upgrade to what would, in essence, be the only supported edition.
With those things in mind, it makes even more sense that Apple made Mavericks free. Internally, it likely argued that the move would not only be good public relations -- as the media coverage attests -- and indirectly contribute to more Mac sales, as analysts believed, but also would focus third-party developers and free its own engineers from pre-Mavericks support responsibilities.
"Free is good," said Craig Federighi, who leads software engineering at Apple, as he announced on Tuesday that Mavericks would come without a sticker price.
Good for Apple, anyway.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is email@example.com.
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