A report has outlined the difficulties micro-blogging service Twitter faces in making sure new members stay with the service.
While it has undoubtedly been the web sensation of 2009, due partly to celebrity endorsement from Stephen Fry and Jonathan Ross among others, 60 per cent of members only stick with Twitter for a month.
David Martin of Nielsen Online, a web-monitoring firm, said: "Twitter faces an uphill battle in making sure these flocks of new users are enticed to return to the nest."
Twitter's retention rate - the percentage of a given month's users who come back the following month - has increased from 30 per cent to 40 per cent.
But when compared with Facebook and MySpace, which both have retention rates of 70 per cent, Twitter faces a struggle.
"To be clear, a high retention rate doesn't guarantee a massive audience, but it is a prerequisite. There simply aren't enough new users to make up for defecting ones after a certain point," Martin pointed out.
However, Nielsen's data doesn't take into account people who use Twitter through other services such as Tweetdeck, which may mean the retention rate is actually higher.