For a description of Twitter's use among the mighty and celebrities, see the article of the Independent, on Thursday 23 January 2009, "Why Britain is suddenly all a-twitter". The Independent joined the club, and opened a twitter "profile"
Given the propensity of users to reveal personal facts, crime could not remain far away. "Twitter hack details revealed" (ZDnet.co.uk, 7 January 2009). The easiness of the hack seemed to be due to a lack of security measures, the login process being easy to break through.
See also, "Hacker used 'happiness' to access Twitter accounts" (CCRC, 8 January 2009). This issue of choosing passwords reminds me of Umberto Eco's novel The Pendulum of Foucault, with the main character trying to log in a (disappeared) friend's computer. At the time, internet was nearly non existent and the password "no" discovered out of exasperation would not sustained the scrutiny of a detection password software.