Apple CEO Tim Cook just left the stage at the company’s WorldWide Developer Conference down in San Francisco. Apple used the WWDC keynote to unveil the next version of its mobile operating system, iOS 6, and announced plans to release Mountain Lion, the next version of Mac OS X, next month as a $19.99 upgrade.

That timing of the Mountain Lion release puts an interesting twist into the longstanding competition between Apple and Microsoft, which is expected to release Windows 8 in the coming months. Apple is focusing on steady improvements in Mountain Lion, such as Twitter and Facebook integration and a new Notification Center for OS X and app alerts.

Microsoft, in contrast, will be asking users to learn a new user interface with Windows 8, as the company seeks to make its operating system work across tablets and traditional personal computers. The Redmond company issued the Windows 8 Release Preview at the end of last month but hasn’t yet given an official release date.

In the realm of video games, Apple will be trying its own hand at something that Microsoft has attempted in the past. The company is bringing Game Center from iOS to OS X with the Mountain Lion release, promising multiplayer gaming across its computers and devices, including iPhone and iPad.

The company says Facebook integration will be added in a future software update to Mountain Lion. Here are the details from Apple’s news release.

“With built-in support for Facebook, you can post photos, links and comments with locations right from your apps. Once you’ve signed in, your Facebook friends automatically appear in Contacts with their profile photos. Your Facebook notifications work with Notification Center in Mountain Lion, and you can even update your Facebook status from within Notification Center.”

Apple also unveiled an overhauled MacBook Pro lineup, making the notebooks thinner and adding retina displays — but targeting them to the high end of the market, starting at $2,199 for one with a 15.4-inch screen.

New features in iOS 6 include deep Facebook integration; a custom-built 3D mapping solution; commitments from major automakers to put Siri buttons on steering wheels; a new “Passbook” app for quickly accessing boarding passes and tickets; and smaller touches such as the ability to quickly respond to incoming calls with preset messages.

The new Apple mapping application marks a break from Google Maps, used in past versions of iOS. It comes with turn-by-turn directions and a flyover feature based on 3D photographic models of major cities.

More: Live blogs from gdgt, Engadget, and Gizmodo.

Apple news releases:

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