According to McAfee and I will quote:
December 16, 2008: Microsoft has announced an out-of-cycle patch release for a critical, remote-code-execution, vulnerability in Microsoft Internet Explorer (CVE-2008-4844). The patch, to be released on December 17, will address the vulnerability across multiple versions on Internet Explorer running on supported Windows platforms.
[via McAfee Threat Center]
[ad#ad2-right]From what I am understanding it will be KB961051 and will be a critical update on all Windows platforms. Microsoft issued a security advisory for this on there Technet support website. This will probably be put online sometime tomorrow and will be available to download after 10am PST although this is just a rumor because when I go to that article they talk about the work around and how to fix it temporary until they release the patch. This is releated to the IE Vulnerability that is in the wild and has been causing havok on the internet.