Good Question.
My answer. The art of conversation.
"But how do you explain the lack of control for the message"? Hmmm....
THE OLD WAY - Let's call this the press release

Here you have a music company putting out the "message" via a traditional route (tv, print, radio). Maybe they reach a musician or someone interested in music, maybe they don't. Once the message is out maybe it's understood, maybe it's not. These "consumers" (maybe they are maybe they aren't) then converse on the topic. Does the music company care to know what they're saying? Can they hear them? If mud gets slung around, how long will it take to repair?
This is controlled?
The two-way conversation - Blogging

Here we have a progressive music company who blogs. They have a constant following of interested musicians and music lovers who network with each other via their site. The company can then put out messages and news to a captive interested audience at any given time. The message is then spread through the audience, while the company has the chance to not only hear the feedback but quickly respond if need be.
All is well on the farm here.
Funny how tradition is comfortable even when it doesn't make sense.
The key to making it work is paying attention to your audience. It may be via your blog it may not. Don't you want to control the message? You'll have to find it first.
Be pro-active, involved, and responsive.
