c2033f7d_ove_the_Crowd___By_Bill_Gurley__Metric_
[Comments:] Leaving Facebook is possible, but finding an alternative with all your friends on it is not really possible. Obviously, the inclusion of Timeline works to increase this even more by creating a permanent dependence on past content. Also, Facebook’s DAU number is staggering. Over half of all users check-in daily. That is uber lock-in. [Grade:] A+ [Metric:] 
Customer Lock-In / Switching Costs
Why Facebook Clearly Belongs in the 10X Revenue Club | Above the Crowd | By Bill Gurley
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