|People using the latest version of OS X Mountain Lion are beginning to see an "Open in iBooks" buttons on iBookstore pages within iTunes, users say. The button appears if a person has a title in their iBooks library, but is currently non-functional, since the first Mac version of iBooks is only due to launch alongside OS X Mavericks. That may suggest, however, that Apple is making final preparations for Mavericks' release.
Apple is expected to announce a final date for Mavericks as a minor item at its October 22nd press event. The OS will likely reach the Mac App Store and new Macs within a week of that date, since Apple has a Q4 financial call scheduled for October 28th, and OS X updates have been timed to coincide with quarterly calls in the past. Apple is also forecast to reveal new Macs on the 22nd, which will likely ship with Mavericks pre-installed.