Maybe someone can make an online quiz of a bunch of formats and accumulate statistics on how well people can actually tell or if it’s just a bunch of random.
There are a bunch of online tests that help you see if you, with your ears and equipment, can tell the difference. http://abx.digitalfeed.net/ and http://abx.digitalfeed.net/list.lame.html was on HN some time ago, for example. I'm not sure if any of them collect stats though.
