According to an article in the New York Times, Apple is aiming to tie their Mac line of laptops and desktops closer to their Iphone and Ipad products. To do this they are making the operating systems on the Mac more like IOS on their Ipads and Iphones. Apple hopes that this will result in consumers coming to the conclusion that since they have an iphone or ipad, they should buy a mac computer instead of a Windows PC. If they have a Mac but are looking to buy a tablet or smartphone, they might as well get an iphone or Ipad. Their latest operating system, Lion, will soon be updated with their Mountain Lion operating system. With this update apple will make the changes necessary to make Lion more like IOS on their smartphones and tablets.

Source: http://www.nytimes.com/pages/technology/index.html