Definition:
Through a marketing perspective, it is the ability to effectively engage and have an active conversation with a respective target audience by providing value and useful information via a conversation.
Expectations:
To gain feedback. To have a conversation to obtain insight for new products/services.
Examples:
There are multiple vehicles each with a different approach: Facebook, Twitter, Google+, Instagram, LinkedIn, etc.
Frequency:
Daily, multiple times per day for some of the platforms. For example, Twitter can be done up to 10-20x/day, where as LinkedIn can be done once a day or week.