We're getting multiple reports of a fresh vulnerability in RealPlayer.  We understand there is some active exploitation of it.  Details:
http://www.securityfocus.com/bid/26130
http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9043319

http://www.symantec.com/avcenter/threatcon/

http://www.avertlabs.com/research/blog/index.php/2007/10/19/realplayer-zero-day-exploit-hits-the-web/

Many thanks to Matt, Jay, Lars, Nate, John, and Jim for bringing this up.