Apple's Mac OS X Mountain Lion is expected to be released this summer.

Apple's responding to more than address book security and working conditions issues this week.

The team in Cupertino, Calif.,  announced today the next version of its Mac operating system: Mac OS X 10.8 Mountain Lion. Released today for developers, Mountain Lion will be available to the public late this summer at the Mac App Store and on new Apple laptops and desktops.

While Apple's current operating system Lion came out only seven months ago, Mountain Lion adds many more  features, many of which were  inspired by Apple's iPhone iOS.

Here's a peek at what Mountain Lion will bring:

Messages - Apple has long bundled its iChat messaging service on Macs, but it will replace that software with Messages, which ties in with iMessage, which hit the  iPhone and iPad last year in iOS 5. Not only will you be able to message with your friends on their phones while you're on your laptop or desktop, but you can also chat on popular instant messaging programs, such as AIM, Yahoo and Google Talk  from the same program. Basically, Messages is an  instant messaging and texting command center. The beta version is  available today from Apple.

Game Center - This is another new feature that Apple's bringing over from the iPhone and iPad. The gaming social network will let  you play games with friends,  who may be on their iPhone, iPad  or Macs.

New Notifications - Apple  integrated  notifications in iOS last year, and now its Notification Center heads to the Mac. Alerts for new messages, calender appointments, Twitter updates and more  appear on the screen, and you can swipe them away almost as easily as you do on your phone, except here you've got to use the  trackapd.

Other additions - Of course, there's tons of other useful additions, including a new reminder app that syncs with your iOS devices.

Apple is also addressing security head on with  Gatekeeper Security, a new piece of software that gives users control over what apps can be downloaded and installed on their Macs.

Apple has not yet said what Mountain Lion will cost. The price is $29.99 to upgrade to the current Mac OS,  Lion.

There are some great first looks at Apple's new operating system at The Verge and Laptop Magazine.