Originally Posted by Acting Like Godot
One big difference is that central banks are not commercial organizations. They are generally created by an act of statute (i.e Parliament or Congress created them) and their staff are all government employees. They are not-for-profit organizations.
Of course, I can speak for every central bank structure, but in the U.S., this is not entirely true. The Federal Reserve Board has stockholders, and is guaranteed a 6 percent profit (though on exactly what, I'm still trying to figure out).
Oddly enough, there are a LOT of people, seemingly, who fight to death the idea that it's otherwise, and others who are quite adept at keeping that information obscured.