This release adds support for running Commerce Server 2007 Developer Edition and the business user applications on Windows Vista. There are also performance and security enhancements as well as fixes for several known issues. To download the bits, please go to
http://www.microsoft.com/downloads/details.aspx?FamilyId=748049C5-A9BF-4AEC-91A0-AFE2DE0BF860&displaylang=en
An updated version of the Partner SDK is also available
http://www.microsoft.com/downloads/details.aspx?FamilyId=BDEA4873-2C06-4C7F-AD51-830A0309FECC&displaylang=en
A list of fixes that are included in Service Pack 1 is provided at: http://support.microsoft.com/default.aspx/kb/939283/en-us