I'm not sure that any of us has a responsibility to be out of the broom closet, after all many have their reasons for being in there in the first place. And perhaps it is for the greater good that they do not readily reveal themselves. It could be environment, it could be peer pressure (family OR friends), it could even be work related. There are quite a few reasons.
I would say the responsibility comes once one has left the broom closet and closes that door behind them. We must represent our craft with responsibility and integrity. This is not to say we scream from the rooftops, or throw up adverts etc. Instead, we carry on with our lives as normal and if we are open, we don't make a big thing about it. If we treat it as an everyday thing, it becomes the norm through time. No need for pointed hats and such.
C_A described responsibility very well when he mentions about dressing normally, instead of the fluffy emo/goth with tats of Aztec calendars on their foreheads, and upside down pentagrams on their cheeks etc. proclaiming the imminent arrival of the spaghetti monster. Calm and self assured with confidence. Acceptance takes time, especially since it has been the "evil step mother" for so long.
I wear a pentacle round my neck, I wear it with pride on the outside of my shirt. I never have a problem (where I live we are more accepting of such things). I have held discussions with Jehovah Witnesses, with Mormons, and with a few others plying their path, but I've never had a problem with them. More often than not we have a good chuckle and a chat.