On Thursday (Aug 8) Microsoft announced the forthcoming content for Patch Tuesday – Aug 13, 2013.
Number of Releases: 8
Critical Security Updates: 3 addressing vulnerabilities in Windows, Internet Explorer, and Exchange Server 2007/2010/2013.
Important Security Updates: 5 addressing vulnerabilities in Windows.
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 Aug 14, 2013, at 11:00 AM Pacific Time (US & Canada).
Register now for the July Security Bulletin Webcast. After this date, the webcast is available on-demand.
You can also follow the MSRC team at @MSFTSecResponse.
Updates are typically released by Microsoft at 10am PDT (5pm UTC).
Configuring WSUS servers to synchronize relative to that time can be helpful in expediting availability of these security updates.