"Application Compatibility Testing and Mitigation Guide for Windows XP Service Pack 2" is now available here. From the abstract:

Windows® XP Service Pack 2 introduces a number of security features and technologies to help protect against attacks on computers running Windows XP. This service pack enables administrators to implement new security configurations that affect the operation of the computer as a whole.
The enhanced security features in Service Pack 2 require you to plan and test your deployment to ensure application compatibility. If application compatibility issues arise, however, it may not be possible in the short term to reconfigure, redevelop, or upgrade the application to operate successfully with the enhanced level of security. The Application Compatibility Testing and Mitigation Guide for Windows XP Service Pack 2 describes the enhanced security features, potential application incompatibilities, and methods of mitigating issues that may arise