constructor should be protected or private. see http://stackoverflow.com/questions/7256530/singleton-protected-vs-private-constructor.

Also, I'd prefer it if we move away from singletons in the future. I know that we've historically used them, but I also know that lots of people say things like in the above article: "Using singletons is bad. Period."

A related article of why they're bad (that I'm reading now): http://blogs.msdn.com/b/scottdensmore/archive/2004/05/25/140827.aspx