The folks at the Visual Complexity blog posted a contribution today by one of their readers. It is a visualisation of over 700 posts to the blog, which lets you browse by keyword and association. Fair warning - you’re likely to waste of time here being gobsmacked by all the great information presented. 

So how do real businesses use twitter? Here's one example, Best Buy has introduced their "twelpforce" campaign. You can send tweets directly to associates with customer service questions. Best Buy's reputation, particularly for customer service, has suffered in the last decade or so. In the last couple years they have launched a lot of innovative programs to turn the reputation ship around. If they keep at it I think they can get their reputation on the upswing again.