After my morning pot of coffee, I cruised past the ENDO blog and saw a video of a law student defending his right to OC with a police officer. The kiddo wins because he's a law-abiding citizen and he knows a lot of case law. OC should be accepted and should be inoffensive to the public. But it isn't. If you open carry, you should be prepared to deal with a shitstorm.
First, almost no cops know gun laws. Second, almost every cop assumes you're lying to them because 99.9999999% of people they talk to are lying. Getting a "man with a gun" call is about as bad as it gets. And since cops work almost exclusively with turds, they assume the "man with a gun" is a "turd with a gun". That doesn't make it right, but that's what you'll be dealing with.
Also, the public outside the "gun community" gets their firearms education from the left-wing media, so not only do they not know gun laws, they assume all gun owners are murderous hillbillies. If you walk into Starbucks with you H&K in a big leather holster outside your shirt, people are going to start dialing 9-1-1 faster than you can say "grande mocha latte". Hell, I've even run into gun store employees who don't know the first thing about firearms laws. When I was 18, I bought a Lee Enfield Mk4 No1 at a gun show, then went back to the hardware store near my hometown to buy ammo and was refused! The store owner said that no one under 21 was allowed to buy rifle ammunition by federal law. I protested, and he called the cops to get an answer. The officer on the scene had to call his supervisor because he didn't know the answer either. If the general public and Joe Law Officer don't even know the basics, they will probably have a stroke trying to learn the rest.
I say all this as a fireproof blanket for the ensuing flame war. I think a lot of guys who OC do it for the attention. Not all, but some. If you OC and someone calls 9-1-1, you get to be Rosa Parks for a day, and fight the good fight for civil rights. There's a time and place for open carry, like camping or hiking. But do it downtown and someone's going to call the cops like the West Hollywood Shootout is starting all over again.
Open carry should be more widely accepted, and the only way to do that is to fight an incremental battle for gun rights just as the left has done against gun rights for the last few decades. But even one day, when you can walk out with your Glock out, I still think open carry is a bad idea.
If you're carrying a gun for defense, you just told every criminal near you that you have a gun. Fine. It may even scare some of them off. But then you might find a brave criminal who thinks your H&K would look great in his waistband and will formulate a plan to get it from you. After all, most gun guys (like me) are big, fat, and tactical. And therefore not very scary to a violent and motivated tweaker. A gun is not always a deterrent, and should not be your first and last line of defense. My defense plan starts with me looking totally unremarkable, not walking around essentially shouting "LOOK AT ME! I HAVE A GUN! KILL ME FIRST IF YOU PLAN TO HARM MY FAMILY".
I'm all for gun rights of every kind, I just don't think there's any advantage to open carry. Even if it were accepted as widely as state tyranny is.