Nielsen Online produced numbers that there are more people leaving Twitter then staying around. The claim is most people are not joining for more than a month. The number is higher than sixty percent of Twitter’s U.S. users don’t return a month later, based on an analysis of traffic trends. The flaw in the report is it only measure traffic on the Internet as opposed to blackberry, iPhone and other mobile devices. This numbers could be bogus as users sign up on the Internet and then use Twitter from a device. There is also another huge segment of Twitter users who just follow and do not post tweets but follow celebrity and retail twitters. The real numbers do not lie as Twitter has grown quite an impressive audience. In March, the San Francisco-based service attracted a U.S. audience of 13.9 million. The same time last year there were only 500,000 users. These numbers will even be higher in April as the Oprah/Kutcher/King race was adding new members as they pushed to be first to one million. This is a big issue as if Twitter cannot user interest, FaceBook and MySpace did not have this kind of issues retention numbers. They also had not seen this kind of growth.