On Thursday (Apr 4) Microsoft announced the forthcoming content for Patch Tuesday – Apr 9, 2013.
You can have Microsoft's security bulletins sent directly to you:
To receive automatic notifications whenever Microsoft Security Bulletins are issued, subscribe to Microsoft Technical Security Notifications.
Microsoft also hosts a webcast where they discuss the releases, typically the Wednesday after Patch Tuesday:
Microsoft will host a webcast to address customer questions on the security bulletins on April 10, 2013, at 11:00 AM Pacific Time (US & Canada).
Register now for the April Security Bulletin Webcast. After this date, this webcast is available on-demand.
You can also follow the MSRC team at @MSFTSecResponse.
Number of Releases: 9
Critical Security Updates: 2 addressing vulnerabilities in Windows and Internet Explorer.
Important Security Updates: 7 addressing vulnerabilities in Windows, InfoPath 2010, Sharepoint Server 2010/2013, Sharepoint Foundation 2010, Groove Server 2010, Office Web Apps 2010, and Windows Defender for Win8/WinRT.
Updates are typically released by Microsoft at 10am PT (6pm UTC).
Configuring WSUS servers to synchronize relative to that time can be helpful in expediting availability of these security updates.