"What's also troubling security researchers is that the password database contains entirely unique passwords. It's unclear whether the people who leaked the password file have more passwords that have not surfaced online. The file may, for example, be an attempt to crowd source the hacking of some of the more difficult passwords."

Well Per Thorsheim called that one!

Edit: "Motherboard conversed with someone at LeakedSource who claimed that they managed to crack 90 percent of the LinkedIn passwords within three days. Though LinkedIn says it has hashed and salted its stored passwords for several years now"

http://venturebeat.com/2016/05/18/linkedin-resets-passwords-...