Facebook login provides the holy grail of that: a (likely) real user behind an anonymous nickname. You can also judge the user by how many friends they have on

Facebook login provides the holy grail of that: a (likely) real user behind an anonymous nickname. You can also judge the user by how many friends they have on FB, in terms of whether they're likely to be a real person. That said, some developers hate using FB for anything, and some users hate connecting with their FB accounts.