People are more likely to purchase things that come from the recommendation of their friends and family.

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This outreach was one woman making a recommendation to her close friends magnified to the highest levels allowed through the global reach of the web.

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And since one of the primary ways that social services grow is through the recommendation of a content shared from friends, colleagues and acquaintances, a paywall can be a serious inhibitor to growth.

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I'm also pretty sure I know my friends, and if I am looking for a recommendation on something, I'll hit particular ones up based on what I know of who knows what.

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We haven't played enough tracks yet to use the "picks" recommendation feature yet (Microsoft's Genius killer), but we usually prefer the recommendations of friends and critics to cold, heartless pieces of software -- and Zune has had that locked down with the Social for a while now.

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