Social login platform Janrain has released some interesting information which analyzes social login and social sharing preferences for online users from the over 365,000 sites using its Engage platform.
As you might expect, Facebook is the most popular option, coming in with a majority of usage at 45 percent - but don't count out Google, Yahoo! and Twitter. The Janrain research indicates that Facebook's share of social logins has increased considerably over the past two years at the expense of Google (and by the looks of it Yahoo!) but as Google+ continues to scale up, that trend seems to be reversing slightly (see graph).
JanRain also analyzed four industry verticals (media, entertainment/gaming, retail, and music) and found similar "arcs" but there are some consistencies across all verticals.
The e-commerce/retail vertical in particular is quite interesting. While Facebook's dominance has declined moderated from 49 percent to 42 percent during the past two quarters, there appears to be a uptick in the most recent quarter. Google seemed to peak in the fourth quarter (coninciding perhaps with the release of Google+) but is has since fallen off. Yahoo fared best in the e-commerce vertical but its slide since 2010 is quite apparent.