This month's Patch Tuesday will plug up less than a dozen vulnerabilities -- 11, to be exact -- in various flavors of Windows, Microsoft Office, Internet Explorer, and other software, Microsoft
announced in a Security Bulletin Advance Notification for April 2012. Microsoft issued half a dozen bulletins in all, the same number as last month, though all but two are rated "Critical" this time around.
All four Critical bulletins deal with remote code execution, one of which affects every version of Internet Explorer (6-9) on various platforms, including Windows XP, 2003, 7, and 2008, regardless of whether you're running a 32-bit or 64-bit build.
The remaining two bulletins are both deemed "Important," one of which is based on information disclosure in Microsoft Forefront Unified Access Gateway, and the other due to remote code execution in Microsoft Office. If you're planning to install them all on day of release, be prepared to restart your system, as two of them will definitely require a reboot and the other four may or may not, according to Microsoft.