In 2010 Mark Zuckerberg said, “If I had to guess, social commerce is next to blow up.” He was right. Social media has changed the way we shop online, and the statistics confirm it. About 81% of consumers receive advice from friends and family relating to a product purchase through a social networking site. And the majority — about 74 % — of consumers rely on social networks to guide their purchases.

About 81% of consumers receive advice from friends and family relating to a product purchase through a social networking site. And the majority — about 74 % — of consumers rely on social networks to guide their purchases.

But the shift from e-commerce to s-commerce has only just begun. Revenues for the social commerce market are expected to reach $30 billion by 2015. This is due to multiple factors, including consumers spending more time on social networks, brands targeting consumers in the news feed (as opposed to fan pages) and advances in technology, such as mobile geo-location shopping apps and enterprise marketing tools.

But who’s vying for this space and what are they doing right? Here are four startups that are making e-commerce social in revolutionary ways.

via 4 Startups Revolutionizing Social Commerce.