The software affected in this update:
- Windows (XP SP3, Vista, 7, Server 2003/2008)
- Windows Remote Desktop
- Internet Explorer
- .NET Framework
- Windows Lync
- Microsoft Dynamics AX Enterprise Portal
Several will require a restart.
The majority of the patches are for IE vulnerabilities, so they are important.
Source:
http://www.neowin.net/news/patch-tuesday-microsoft-fixing-27-vulnerabilities