Social networking B2B vs. B2C
B2B companies who are using social networks are more active than B2C counterparts. This is most visible in microblogging, discussions on third-party sites, blogging and monitoring their social footprint on different sites. B2C companies are ahead in a few areas: social media advertising, user ratings and reviews, and online communities for customers and prospects.
Some pretty interesting stats from emarketer.com.