I personally don't believe in open carry as a deterrent. I don't think any criminal around is going to be deterred by knowing a weapon is present. If somebody is mentally screwed up enough to make a target of a person without knowing if they're armed or not, announcing to them that you are only gives them an upper hand.
But open carry shouldn't be used as a deterrent in the first place. It is a statement to the public that carrying a firearm isn't a crime. Too many people don't have the slightest clue what is legal when it comes to firearms and assume the only people carrying are cops and criminals. Open carry should be about peacefully expressing your stance on gun rights, not about deterring criminals.
I also don't like the types who open carry with a camera with them hoping they'll get stopped by an officer so they can video tape said officer and put the video online. You don't need to immortalize some poor officer on the internet to make a point and let him forever be seen as the villain. But I suppose that's an issue for another time.
"Intelligence is nothing more than discussing things with others. Limitless wisdom comes of this." - 山本 常朝