LinkedIn recently published some stats you should be aware of.

• Total number of U.S. users is 154 Million
• 40% of users visit site every day
• 70% of Total Users are outside the U.S.
• Total users Globally 590 Million
• Monthly Active Users: 260 Million
• 39 million students and recent grads
• Profiles with professional headshots get 14 times more profile views.