[bjourne]

Building using a keyboard shortcut from within an IDE is just one of the many tasks a build system is required for. Another is setting up a build server that builds the projects on every checkin, deploys it on the various test servers and runs all the test suites. That requires the build system to be scriptable, idempotent (as in weird stale cache issues won't screw up your builds) and easily controllable from the command line.

MSBuild completely sucks at these tasks when compared to any free software build system such as Ant, Automake, CMake, WAF or dozens others. It was designed to be used in conjuction with Visual Studio and you very much feel the limitations of it when you try to use it from the outside.