As did the major social networks like Google + Facebook,
Pinterest now, probably the fastest growing social network, today announced that opens to all users permanently leaving behind the invitation system.
The invitation system works since April 2011, and although most users that they wished they had just being able to access the network, was an entry barrier that prevented further expansion of the social network. Now with the opening, not only opens to all users who want it easy but allowing login access via Twitter or Facebook or, as always, using a validated email.
If Pinterest recently took a big step forward with his version in Spanish, openness to all users who wish was probably what slowed the leap from social network in 2 years, has been ranked as number 38 of the web world ranking in June 2012 and 16th in the U.S., just behind Bing.
La Teva Web at Pinterest