Stowe Boyd does a powerful job of framing the powerful flow of new media channels in this article, and I recommend reading the insightful comments as well.
When planning the marketing of an enterprise, we have both defined audiences (a contact database) and undefined audiences (both people who are influenced by our contacts and people who are looking for us). By using both direct and distributed media, including email, direct mail, blogs, Facebook and Twitter, we are setting ourselves up to grow in both the depth and breadth of our market.
/Message: The Business Case For Streams versus Email, 2010-Jun-16, by Stowe Boyd
Email is addressed, stream posts are released.
Email is private, and the distribution of messages is determined by the author at the time of writing. Individuals may decide to block my messages, but they can t opt to see all of them. This means that the effective use of the information in the message is based on the premise that the author knows who should read it.
Streams are public within some defined public , and the distribution of messages is determined by the actions of all the members of that public. Individuals decide who they will follow, and the collective streaming of information is the result of the affiliation of all the members of the public.
In the context of business, this means that email is selective: the author selects who should read the message. Streams are elective: the eventual recipients of messages elect to receive them.