I have received several comments on my XPSP2 post regarding issues from our changes regarding raw sockets.  I am very much not an expert on raw TCP sockets, but I certainly know people who are.  If you are having a serious issue as a result of this change, please send me a note via the 'Contact' link on my blog page.  Once I have your email and issue from there, I will be happy to put you in touch with people who are far more knowledgeable on the topic than I.