I was reading there is a new command line switch to pass in ProductVersion as part of the build. Is this supported by the MSBuild task? I don't have VisualStudio installed on my clean machine with IS2008 so I can't tell what changes were made to the ISPROJ files.
Currently I have a custom MSBuild Task written in C# that I use to override the BeforeCompile target. The task updates the IS XML before building the solution. It would be nice to just define a property with the version number and build the solution without any additional plumbing.