This from tweetie and the brain an interesting look at how Dyson is speaking to customers with Twitter
You have to be on form ALL THE TIME now. If you drop the ball ONCE the democratized voice of the internet can use it against you forever. But not playing is also not an option - your competitors are or will be using social channels to build an adoring customer base, spread their message, correct inaccuracies and have fun! (all hail @zappos). Your only defence is sticking to strong core principles such as openness, honesty, civility and genuinely caring about your customers.
That last comment really highlights why we need to finish up our brand work:-)