Formerly the content known as the Windows Vista Jumpstart Kit can now be found on MSDN under the title Windows Vista Application Comptability.
This content is intended to help educate ISV’s on new features in Windows Vista that might affect Windows XP applications. It contains White Papers, Power Point slide, tools, and videos intended to help the ISV determine if their application will be affected. Additionally, this info will show how to fix the issues once they have been discovered.