Only 66% of users on complex payment systems will complete a transaction - making cart abandonment a major issue for ecommerce sites. Amazon thinks it may have come up with a solution. The problem, they discovered, is that users who needed to log in with an Amazon account kept forgetting their credentials. So, logging in to complete the transaction became one of the points of abandonment. By simplifying this process - i.e. giving users the ability to log in with their more memorable social account credentials - they've found that conversions are increased by 50%.
Users on WebmasterWorld are somewhat skeptical. User Shepherd says that this "might also make it seem like using a social login helps with conversion rate but really just [stops] people who never had intentions of buying from setting up an account." User keyplyr comments that there could be security risks associated with linking social profiles to Amazon - are the risks worth the rewards?
Other users wonder if Amazon is really the best company to emulate. They're larger than almost everyone out there, they have amazing brand recognition...the results on a smaller ecommerce site could be wildly different. Thoughts?