Is the emergence of social media changing the way businesses are run? Is this becoming a differentiating factor for companies?

Yes

social media emergence has certainly added value.sales,marketing,customer services,and business development has certainly been transformed  and are now running on high alert.

unfortunately social media has con's and pro's.one must be carefull of customer feedback or ratings as negative customer feedback  can damage your reputation.

i believe the pro's over weight the con's.