Where do you get your social media links from?

Recently I was looking at my link structure and was looking at the social media links.  I was suprised to have over 1000 from pinterest and only have 30-50 from Facebook and Twitter.  I was curious if other people see the same thing.  I personally do not use Pinterest so I am not sure of the popularioty.  I know it is popular, but did not realize it would get you that much more mentions than Facebook or Twitter.