For many of my ISV, working great with Service Pack 2 is an important step for this year. I am pleased to say that the Application Compatibility Testing and Migration Guide for Windows XP Service Pack 2 is now live

http://www.microsoft.com/downloads/details.aspx?FamilyId=9300BECF-2DEE-4772-ADD9-AD0EAF89C4A7&displaylang=en