All Apple Mac OS X users should update their systems as prompted. There were 53 issues addressed in several components including third party software
Apple Mac OS X – Security Update 2011-001
Mac OS X v10.6.7 and Security Update 2011-001
QUOTE: This document describes the security content of Mac OS X v10.6.7 and Security Update 2011-001, which can be downloaded and installed via Software Update preferences, or from Apple Downloads.