I agree, because both benefit from expanding their userbases, in terms of increasing exposure for ads (as well as those on the receiving end of LinkedIn's paid

I agree, because both benefit from expanding their userbases, in terms of increasing exposure for ads (as well as those on the receiving end of LinkedIn's paid InMails, etc.). Both companies are only touching the surface of generating revenue from their mass of users, with new innovative models beyond simple advertising and subscription features. I like UpDown.com's approach to taking the decision making power of the crowds and extrapolating it into an offline business model. For UpDown, expanding userbases online drive growth in exposure revenue (ads) and increased decision making power for the offline half.