Last night, Apple published OS X 10.8.2 Supplemental Update 2 for all Macs released during 2012, the update solving the problems that some encountered when trying to use the Keychain. Apple does not specify whether other bugs were solved by the update or whether other improvements were made to the system, but if you bought a Mac this year, it is advisable to install the update that you can also find in this page.
About OS X Mountain Lion 10.8.2 Supplemental Update 2.0
This update addresses an issue with Keychain that can affect 2012 Mac systems.
This update is recommended for all Mac systems introduced in 2012.
