Significant in that the title is "Pinterest Passes Twitter In Popularity..." so if you decide to judge popularity by page requests then I suspect twitter may be

Significant in that the title is "Pinterest Passes Twitter In Popularity..." so if you decide to judge popularity by page requests then I suspect twitter may be more 'popular' than Pinterest. This theory is backed up by http://www.alexa.com/topsites/global;0 http://www.alexa.com/topsites/global;0 where Twitter is 12th and Pinterest is 30th. Of course, popularity doesn't pay the bills!