Should I be building 2.50.x or master (I'm still not clear on the difference? master is a rewrite-in-progress, if I understand correctly?)

Are there instructions somewhere on the dependencies needed to build the source?

I see an MSVC2008 project file; are there project files for MSVC2010 or 2015/16? Are there any plans to deprecate 2008 support and switch to 64-bit C++11?

I see some discussion on GitHub about switching to CMake. That sounds like a good idea -- what is the current status of this?

Sorry for all of the noob questions -- I've been out of the loop for a while. Feel free to just point me to a FAQ to read if my questions are answered there.