has had this functionality for months now...
http://www.metasploit.com/modules/exploit/windows/fileformat/adobe_pdf_embedded_exe
Now, it's entirely possible that he found this on his own. But it's not exactly a new development...
Also, before anyone goes and claims to have found a way to get Java applets to execute arbitrary code as well:
http://www.metasploit.com/redmine/projects/framework/repository/entry/modules/exploits/multi/browser/java_signed_applet.rb