Cluetrain might be old news, but exploring role of conversations -- as, within, between, among -- markets is still topical. See Josh Klein's discussion on how companies should decide whether or not to use Twitter, just for example.
No one likes being talked at. Most pitches and presentations fall flat for just this reason. Much better to start a conversation listeners want to continue.
If no one wants about your product to other people (including you), it's probably a good idea to avoid social media.
Silence is always better than spam.