Earned. Most definitely. No one just automatically commands my respect. Anyone that gives their respect away is either very naive or very foolish, if not both. (This is not to say that everyone doesn't deserve common courtesy until they have proven otherwise.)
I don't care if you're the queen of England, the president of the US, or King Shit on Turd Mountain - if you want my respect then you have to earn it.
A dominant deserves only the respect s/he earns. All too often I've seen new dominants stick a "lord", "sir", "master/mistress", "lady" in their name and expect submissives to bow down in front of their overblown egos.
In fact, I'll go so far as to say that someone that tries to demand my respect without first being willing to earn it is not going to get it.