I have a VS 2008 solution that I migrated from FB6 to FB7. With the "Build VS.NET Solution" action, I have the "Update Assembly Info for .NET projects" checkbox checked. I saw that some of the assemblyinfo.cs files were being updated and others were not.
After taking a look, I saw that the projects that the AssemblyInfo.cs file in the project's Properties folder were being correctly updated. The AssemblyInfo.cs files that were the project root folder were not. I was able to move the AssemblyInfo.cs files to the corresponding Properties folder and that fixes the problem for me. This does appear to be a change in behavior with FB7.