Registration forms have always been the weakest link in most lead generation processes. When presented with a registration form, research shows that as many of 75% of site visitors will flee the site instead of completing the form.
But social login web services from LinkedIn, Twitter, Facebook, and Google are beginning to change this equation by providing a simpler login method and thus streamlining the prospect experience. Instead of completing a new form, prospects can quickly login with existing social media credentials.
The Benefits of Social Login: Quick Login & Access to the Social Graph
Sites that offer social Login see increased usage and decreased form abandonment. According to a study by Gigya, site users spend 50 percent more time on sites when they’re logging in through social networks than with a standard login process.
For marketers, social login also offers a wealth of prospect information to personalize the prospect relationship. In the case of Linkedin, social login provides access to contact information as well as public profile information. This information is valuable, and can also be easily kept up-to-date.
The Social Login Dilemma: Appropriate Use of Social Information
While Social Login provides useful data to marketers, it does change the natural give-and-take of personal data exchange in a way that can cause problems. When most people fill out a form, they do so knowing that the information they provide may be used to contact them. When they access content via social login, they are likely not aware of the information they are transferring and are less likely to expect to be contacted. If the call from sales is unwanted and unexpected, it can create a particularly negative experience.
For this reason, I typically center my lead generation processes around asking prospects whether or not they would like to be contacted by sales — It’s honest, effective, and allows prospects to choose the type of relationship that they have with your company.
Science of Revenue 
Great article, Paul. We at LoginRadius, have seen drastic increase in user engagement on our customer websites; and I think this is going to be an essential functionality on any web or mobile application as influence of social media increases.