The predicted July 5 release date of Mac OS X Lion by MacTrast turned out to be incorrect.

According to sources of 9to5Mac, the next, more probable release date of Mac OS X Lion is July 14.

The predicted July 14 release date coincides with the expected release of Apple’s new MacBook Air. Although neither release has been confirmed at the moment, the fact that Mac OS X Lion has been constantly marketed alongside the new MacBook Air makes it more likely that Apple will release both products on the same day.

“Other systems are rumored to be arriving soon afterward or even at the same time, such as white MacBooks as well as Mac minis and Mac Pros,” says Electronista.

The OS X Lion represents a quantum leap forward in terms of OS advancement, from the current version of OS X 10.6 (Snow Leopard) — According to the International Business Times.

“While product refreshes are generally a standard practice (faster, better, same cost), we believe the MacBook Airs could eventually replace the traditional white MacBook that remains in the line currently,” said Ben Reitzes, an analyst at Barclays Capital.

The OS X Lion download will cost either $29.99 or $49.99 to upgrade computers from Mac OS X 10.6 to 10.7, at an estimated 4GB in size. According to Apple, buyers are welcome to download the upgrade in any of its retail stores.

Lion can also be installed only on Intel Core 2 Duo, Core i3, i5, i7, or Xeon processors, according to Apple.

Mac OS X Lion is said to include over 250 new enhancements and features.