I like this nifty example of a community web site utilizing social media from Crain's.
The site Detroit Make It Here utilizes multimedia, blogs, twitter and other tools to create networking opportunities intended to "Inform, empower and unite the creative community" of the Motor City.
The Web site is part of Detroit Renaissance’s ongoing plan to market metro
Detroit’s creative scene and urge companies to hire locally for creative
products and services.
Who are creatives?
Just about anybody working in advertising, architecture, arts,
art/historic preservation, digital media, design, engineering, film/video
production, marketing, media, music production, photography, public relations,
urban planning and more.
Like this example from General Motors and the Volt:
The Chevrolet Volt's chief engineer had this job on Tuesday: Type
140-character answers to questions from anyone who had them.
Andrew Farah spent 40 minutes answering questions about the Volt on
Twitter, a social media site that General Motors Corp. joined about a year ago.
Twitter allows users — from the guy next door to President Barack Obama — to
give 140-character news tidbits about their lives.
Using Twitter is an example of how automakers can reach the growing
number of prospective car buyers who get information from personal blogs and
social media sites, according to a study introduced today at the Chicago Auto
Show by market research firm J.D. Power and Associates.