OS X Mountain Lion now available via Mac App Store

John Siracusa’s extensive review of OS X 10.8 is now available as well.

Jacqui Cheng – Jul 25, 2012 7:38 am | 29

Warm up your broadband connections, because Mountain Lion is now available for public consumption. Apple released OS X 10.8 to the Mac App Store on Wednesday morning, less than a day after announcing its third-quarter earnings—just as we originally predicted. The release weighs in at 4.05GB and costs a flat $19.99 for the upgrade, so long as your Mac is supported.

It has been a seemingly short five months since Apple first went public about OS X Mountain Lion. The goal of the release is to bring over many of the successful elements from iOS in order to improve upon the Mac experience—for example, 10.8 includes Mac versions of Notes, Reminders, Game Center, Notification Center, Share Sheets, OS-wide Twitter integration, and AirPlay Mirroring. That’s in addition to improved iCloud support across a number of Apple apps, as well as the ability to use a single sign-in to set up Contacts, Mail, Calendar, Messages, FaceTime, and Find My Mac. There’s also a new feature called Power Nap, which allows your machine to wake itself up to download software updates, iCloud, and back up to Time Machine.

Mountain Lion will also feature Gatekeeper, which allows users to control (via settings) the sources from which different apps can be installed. By default, apps from the Mac App Store and those with approved developer certificates—even if they were downloaded over the Web—are allowed. But users can also opt to allow apps from any source, including shady sites with unsigned apps. When we spoke to a handful of third-party Mac developers in February, most of them seemed cautiously optimistic about GateKeeper, and some even wished that Apple would port such a system over to iOS so that users could have the option to run apps that came from places other than the App Store.

As expected, Mountain Lion is not available on optical media; Apple is distributing the release via the Mac App Store, just as it did with the 2011 release of OS X Lion, but not via USB key like it did last year. If you’re the type who likes to keep backups of your software purchases, though, worry not—Mountain Lion creates an emergency partition on your drive so that reinstallation is easy. (Stay tuned for a guide on how to back up your Mountain Lion installer to your own USB thumb drive, which we will post later today.)

We know you didn’t come here just to read about Mountain Lion’s feature set, though. As usual, we have an extensive review of Mountain Lion written by the esteemed John Siracusa right here on Ars, which will also be available as an e-book for $4.99 through Amazon later today. We plan to have coverage throughout the day of some of Mountain Lion’s headline features, so stay tuned on Infinite Loop!

Update: As of 7:45am CDT, it seems users are getting an error when they try to buy Mountain Lion from the Mac App Store. I was able to start the download, however, so you may just need to try a few times.