Eight in ten people use Twitter for business purposes says the IAB. Lets face it, that's not even slightly plausible.
Reading the article, you find that the Kamaron Institute surveyed three hundred Twitter users, so it should read eight in ten Twitter users.
That's probably about right, when you consider that Twitter is rapidly turning into a tool for the marketing industry to talk to itself and for spammers to talk to the marketing industry.
The IAB has written some guidelines, for brands wanting to use Twitter too.
But I prefer these: http://www.howtousetwitterformarketingandpr.com/