Twitter has a new section on their website offering information on how businesses are using twitter for marketing and customer service.
This Twitter & Social Media Marketing Guide includes recommended books, Twitter definitions, and case studies of businesses using Twitter for marketing:
When people working in the Empire State Building twittered that they were craving ice cream delivery, New York local chain Tasti D Lite was there to listen and meet their need. When electronics buyers look for good deals, the Dell Outlet Twitter account helps them save money with exclusive coupons. …

Definitions of twitter on the Web:

chitter: make high-pitched sounds, as of birds
chirrup: a series of chirps

wordnet.princeton.edu/perl/webwn

Twitter is a free social networking and micro-blogging service that allows its users to send and read other users’ updates (otherwise known as …

en.wikipedia.org/wiki/Twitter

a succession of chirps as uttered by birds; to utter a succession of bird’s chirps; (of a person) to talk in an excited or nervous manner

en.wiktionary.org/wiki/twitter

twittery – that twitters

en.wiktionary.org/wiki/twittery

twittering – twitters fundamental question is “what are you doing?” This is can be in its most simplistic for a one or two word …