My friends ask me often “Why do I need Twitter”. Well maybe you don’t, I don’t know. Not everyone does need Twitter. I use it for 2 reasons: news and information. I get news from the ground from the people who are making the news, not after it’s filtered by news agencies.
On the info thing, I follow people who tweet about things that interest me, and they share links that help me. I read and re-tweet FAR more than I actually tweet.
This article summarizes (very well) the best reasons for using Twitter:
(Don’t you love the image??? I used it because YES Twitter is addictive!!!)