This is nothing new but is still very cool; it has potential applications beyond detecting social sites; detect visitors that have visited competitors, for exam

This is nothing new but is still very cool; it has potential applications beyond detecting social sites; detect visitors that have visited competitors, for example. I think I'll implement it on http://esciencenews.com http://esciencenews.com for the social share section (which has digg, reddit, stumble, etc) because the amount of submissions I see from those buttons is super low and I guess meaningless for 99% of users.