Visual Studio does not intercept std::cout or printf, these get sent directly to the console. To print in Visual Studio's Output window you need to use OutputDebugString. If you want consistent behaviour between Visual Studio and xcode you should use the Log function located in FFGLUtilities.h
It works a bit different than printf, there's no more format flags, you can just do this:
Log( "This is a number: ", 3.14f, " we all love pie dont we?" );