Short news, I’ve just updated and tested GEOS project files for Visual C++ 2005. I added new unit tests to the project. Note, that I created the project with Visual C++ 2005 Express Edition, but you can use it with any edition of VC++ 2005.
You can download the project files for Visual C++ 2005 from my unofficial GEOS repository. After you download the geos-msvc-2005-project.zip package, unzip it and read the README file inside. You only need to checkout GEOS sources from CVS or unpack them from the official archive. Note, that Visual C++ will launch unit tests automatically at the end of building process, as a post-build event.