I recently read this article and love the points the author is making.

a) Do not think of social media as being hierarchical (e.g., speaker/audience); rather, it evens the playing field and makes all things egalitarian in many ways.
b) Step outside the box and innovate! Make people want to respond to you!
c) Be real and transparent online; people can sniff out a con artist or someone that is self-serving. Letting others know your INTENT can help make them CONTENT with your CONTENT.
d) Strive to be considered an expert with knowledge to share. If you are a knowledge broker, you do not have to sell your product or services — they will sell themselves. Rather, be discovered.