The Internet Explorer 0day aka now CVE-2012-4969, have been used in a "small number of targeted attacks". The new Internet Explorer Zero day technical details came out (eromang.zataz.com), the Metasploit module is out now too and the number will increase exponentially as soon as exploit pack authors add it to their arsenal, which will happen very soon. This seems to be repeating the story of Java CVE-2012-4681. See CVE-2012-4681 samples Original (APT) and Blackhole 2.0 (crime)
There are a few mitigation workarounds you can use for now, the best is to upgrade your browser, however
Read more at http://technet.microsoft.com/en-us/security/advisory/2757760