The most idiotic, elitist response you will hear against open carry, mostly from the anti-2nd Amendment subset of the military and law enforcement communities, goes something like: "Concealed is the only way. Maybe loaded open carry, but why would anyone want to carry unloaded? An unloaded gun is useless!"
This is the 2010 version of "Let them eat cake!" Time for a reality check. Here in Orange County, California, many of us had CCW permits for a long time and lost them because of the current sheriff, and because of the law giving her the discretion to take them away (though the discretion was exercised arbitrarily and improperly). Under California law you can carry without a permit where there is an immediate need, but what if a civil disturbance arises and along with it, an uncertain greyness over whether you need to be carrying regularly, even if it's just around your neighborhood? Barring an extremely favorable ruling from the Supreme Court (actually this is a possibility as early as next month), providing us judicially with the sort of "constitutional carry" Arizona recently enacted (nowhere on the California legislative radar, anytime this century), the only way you could carry under such greyness would be to have a concealed carry permit, which is now "cake" for many in Orange County.
And an unloaded gun is, most emphatically, NOT useless. With just a little training, and a single solitary second of time, it can be transformed into a loaded, fight-stopping tool of defense.
And nothing can beat the deterrence value of open carry, or its value in educating the next generation of patriots.