Gigya, a provider of tools for social sharing and third-party logins, took a look at the numbers and found that, since its last round-up of social logins in July 2010, LinkedIn has skyrocketed as the login of choice for B2B sites. According to Rachel Peterson, a spokesperson for the company, LinkedIn has seen increased use as a third-party login ever since it updated its profile API. The site has seen an increase from 3% to 20% in just over six months.

"LinkedIn has a strong case that a single social graph through Facebook is not sufficient," said Peterson. "Professionals want to apply different profile data to business oriented sites and share that content with a different group of people than their FB friends."

So, if you're thinking of taking  your site the way of eHow and forsaking all other logins for the one, true Facebook login, you might want to take a gander at the following graphic and see where your visitors lie. Maybe you should be working on that LinkedIn presence a bit more and Facebook a bit less.