Buy OS X 10.8 while you still can

While Apple recently instituted a policy of offering older versions of an app to users on older versions of iOS, it does not have the same policy on the Mac App Store and has so far given no indication that it will make older versions of OS X available upon the release of Mavericks. Consequently, the moment OS X 10.9 is released (possibly tomorrow), OS X 10.8 is likely to cease to be available for purchase.

Sometimes it can be difficult to juggle the OS compatibility of multiple third-party applications, particularly if you are still using deprecated apps in your workflows (e.g. FCP 7). So even if you have no plans to install it any time soon, we'd recommend buying OS X 10.8 Mountain Lion on the App Store today so that you have it tied to your account for future use.

Update: While 10.7 and 10.8 are no longer available for direct purchase from the Mac App Store, Apple is now offering redemption codes for OS X 10.7 and OS X 10.8 on its main online store.