Linkedin Premium: is it worth $39.95 a month?

Linkedin now is trying to monetize itself by asking users to upgrade to Premium. It seems the main advantage is that you can no longer send “InMails” to other Linkedin users unless you have a premium account. This page lists the benefits of their various Premium plans and the extras they get you versus what comes with the free Basic plan.

I can’t fathom paying $40 a month for an email account I can only use within a single service provider. Am I missing something that’s extremely useful in the other benefits, or is Linkedin Premium as dumb an idea as it seems?