FORTUNE -- The report issued Thursday by Chitika Insights calls it "the power of free" -- a reference to the price Apple (AAPL) charged Mac users to upgrade to Mavericks, the latest version its flagship operating system.
Sampling its ad network last week -- five months after Mavericks' release -- Chitika found that 40% of its clients' page views were coming from Macs running Mavericks. That's six percentage points better than Mountain Lion ($19.99) reached on the same ad network after nearly 14 months.
It may be a record for a computer OS. Nine months after Windows 8 came out, it still hadn't achieved 5% penetration (see here).
But 40% pales compared with the upgrade rates on Apple's smartphones and tablets, where after six months, iOS 7 users were generating more than 80% of Chitika's iOS Web traffic in the U.S. and Canada.
"That disparity," Chitika suggests, "is likely at least partially a function of the nature of the desktop marketplace, where computers are typically kept for a longer period of time as compared to mobile devices, and hence may not necessarily be upgrade eligible. Additionally, a larger and much wider range of users in terms of economics, age and other factors regularly browse using desktops and laptops as opposed to smartphones and tablets, which have user bases skewed more tech-savvy as a whole. Finally, unlike on iOS, where users receive a direct prompt to upgrade to the latest OS version, Mac desktop and laptop users were not actively solicited to update to Mavericks."
Also Safari, Twitter, Calendar, iBooks, FaceTime, Keynote and Software Update.
FORTUNE -- Ashkan Soltani, an independent computer security expert best known for analyzing Edward Snowden's NSA leaks for the Washington Post, has published a list of applications running Mac OS X 10.9 that he says are vulnerable to the same security hole Apple (AAPL) patched in its mobile operating system on Friday.
They include apps used by millions of Mac users every day: MOREPhilip Elmer-DeWitt - Feb 24, 2014 9:56 AM ET
Harvard's Lawrence Lessig puts his finger on the problem with Apple's software updates.
FORTUNE -- I was lucky. As soon as they were available, I installed Apple's (AAPL) new software suites on all three of my workday computers -- iPhone, iPad, MacBook Air -- and have yet to come across a stumbling block serious enough to prevent me from doing my job.
Harvard Law professor Lawrence Lessig -- one of the most MOREPhilip Elmer-DeWitt - Nov 4, 2013 8:03 AM ET
New iPads, OS X Mavericks details, and more? Our look at the odds of each being announced.
FORTUNE -- Apple (AAPL) faithful, get those credit cards ready. On Tuesday, the company is holding an event in downtown San Francisco that will almost certainly mean the unveiling of all-new iPads. But what else will Apple trot out? New Macs? New iPods?
We won't know for sure until 10 am Pacific/1 pm Eastern tomorrow, but here's MOREJP Mangalindan, Writer - Oct 21, 2013 11:30 AM ET
The venue -- in San Francisco -- is larger than the site of last month's iPhone event.
FORTUNE -- What might Apple (AAPL) have up its sleeve for the Oct. 22 event it announced Tuesday? Among the rumored new products:
The iPad 5
The iPad mini 2
The new MacPro
Mac OS X 10.9 "Mavericks"
Anything I've missed?
UPDATE: For a round-up of the rumors, I recommend Neil Hughes' What to expect from Apple's Oct. 22 event at AppleInsider.Philip Elmer-DeWitt - Oct 15, 2013 12:30 PM ET
|Canadians arrest a Heartbleed hacker|
|US Airways won't fire worker who sent lewd tweet|
|5 people you might not tip (but should)|
|Toyota unveils redesigned Camry|
|Google stock sinks after missing Street|