Lion, which is the eighth iteration of the revolutionary OS X format, has become the fastest selling operating system in Apple's history, the company said in a press release.
"Lion is off to a great start, user reviews and industry reaction have been fantastic," said marketing head Phil Schiller.
"Lion is a huge step forward, it's not only packed with innovative features but it's incredibly easy for users to update their Macs to the best OS we've ever made."
The speed of uptake can no doubt be attributed to the new download-only mechanism, with Lion exclusively available on the Mac App Store in 123 countries.
Users no-longer have to traipse to the nearest Apple Store in order to pick up a physical disc and can install from the comfort of their armchair.
An attractive price point of just £20.99 surely helped too.
Lion, which landed on the Mac App Store yesterday boasts 250 new features, including a host of multi-touch gestures and native full-screen apps.
Other highlights include the new Mission Control feature which showcases everything you have open on your Mac, Resume which saves your last activity in apps even when you restart the computer, and Versions which backs-up your documents every time you save.
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A technology journalist, writer and videographer of many magazines and websites including T3, Gadget Magazine and TechRadar.com. He specializes in applications for smartphones, tablets and handheld devices, with bylines also at The Guardian, WIRED, Trusted Reviews and Wareable. Chris is also the podcast host for The Liverpool Way. As well as tech and football, Chris is a pop-punk fan and enjoys the art of wrasslin'.