Political campaigns are being waged, products launched, family reunions staged, and old friendships rekindled. On Facebook. It's no wonder then that the fastest growing demographic of this popular social media site is forthsomethings. And it's us fortysomethings who may have a higher sensitivity to privacy issues than our Facebooking kids. Still though, it's not a bad idea to review some important rules of the road, common sensical as some of them may be, for maintaining your privacy. Boston Globe technology wonk, Hiawatha Bray, has laid them out here.