LinkedIn announced yesterday that they have achieved the 50 million registered user mark!

NB Facebook just hit 300 million users.

You can almost picture the adoption curve; on launch in ‘03, it took 477 days for the first million members to join. I remember getting the stamp ‘1st Million User stamp’ for my profile. The last million took only 12 days!

Everyone said success of social networking would be in niche sites. Linkedin is pure a business site. Most notably mentioned for background verification in recruitment. It’s got a lot of grief for not allowing any old API to do anything they’d like ala Facebook. But with it’s steadfast approach it has earned great respect and the range of ‘high net worth individuals’ registered is enviable.

Congratulations Linkedin on your 50th Million user. May you continue to grow.