On 21st of April 2011 Facebook celebrated the one year anniversary of one of its most important product launches, the Like Button. To commemorate the one year anniversary of the Like Button Facebook released some interesting data about the button's usage in its first year.
1. 10,000 websites integrate with Facebook each day
2. More than 2.5 million websites have integrated with Facebook
3. Over half of the 25 fastest growing U.S. retail sites use Facebook
4. Media sites that adopt the Like button average a greater than 300% increase in referral traffic from Facebook
5. Every month, more than 250 million people engage with Facebook on external websites