Leading B2C (Business to Consumer) companies have invested in Listening Centres where they monitor real-time conversations and web analytics in order to gain immediate insights, start dialogues, diffuse critical issues and observe competitors. They use sophisticated dashboards of real-time information on keyword tracking and competitor share of voice.
Here is a 76 second commercial from Gatorade which gives a high-level overview of their Mission Control approach:
Here is a much more detailed and informative video about the Dell Social Media Listening Centre.
Cisco gives an example from the Business to Business world:
If you want to understand your customers and engage with them then you have to listen and respond. Resourcing this kind of monitoring and response facility is essential for any company.