On public beaches and places like that, women are allowed to go topless where I live. Walking into a store, however, is a different story. But then again, men generally aren't welcome in stores (and other such places) without a shirt either.
So basically, if the topic is asking, "should women be allowed to go topless anywhere?" Then my answer would be no, and neither should men.
I'm going to disagree with the majority, and say that this is a load of crap. It's certainly not against the law here to drive with headphones in your ears, and I don't see why it should be. I've been driving for about 10 years now, and I have never run into any problems because I was wearing headphones. But maybe that's because I actually pay attention to the road; you know, do more than just look straight ahead.
Oh, and in case anyone is wondering: I wear in-ear headphones, and I still hear sirens and shit just fine.