Twitter may well be struggling in its search for a profitable business model, but the company has made an impact on multiple levels of the marketing chain.
Governments have used it to promote both transparency and direct communication with their constituencies.
Academics have used it as an online tool to follow up on research and expert opinions.
Doctors used it as a didactical device detailing every step of a brain tumor operation for students to follow.
Corporations use Twitter for sales pitches.
Small businesses find Twitter useful to keep customers updated.
Amazon quickly responded to a tweeted outcry about their censoring of so-called adult books.
Starbucks did some reputation damage management after it was rumored that the company would stop serving the troops in Iran as a protest against the war.
Dell noticed customers complaining on Twitter that the apostrophe and return keys were too close together on the Dell Mini 9 laptop – they fixed the problem on the Dell Mini 10.