The eMarketer Web site carries a new study from TNS and The Conference Board identifying reasons people are using Twitter. More than two-fifths do so to keep in touch with friends, rather like an extended emailing.

Nearly 30 per cent use it to keep people apprised of their status. Interestingly, though, one-quarter are on Twitter to keep abreast of news. More than one-fifth used it for professional purposes and nearly 10 per cent for research purposes.

Who do you Tweet? Friends and family, mainly. Who got you hooked? One-half said friends and family, one-third said co-workers.