Twitter users are becoming more active, but so too are the cyber criminals targeting the micro-blogging site to infect PCs with malware, according to the latest figures from Barracuda Labs.
The security firm's annual report (PDF) revealed that the proportion of Twitter users with no followers has fallen from 20 per cent last June to 17 per cent today, and the proportion with fewer than 10 followers dropped from 80 per cent to 74 per cent.
Around 27 per cent of users have tweeted more than 10 times, representing a 29 per cent increase since June.
However, Barracuda Labs said that the 'crime rate' on Twitter, which it defines as the percentage of accounts created per month that are eventually suspended for malicious or suspicious activity, is increasing.
The rate was 1.2 per cent in 2006, 1.7 per cent in 2007 and 2.2 per cent in 2008, but had jumped to a record 12 per cent by October last year, according to the research.
Barracuda Labs also claimed that just 21 per cent of people using the micro-blogging site are "true Twitter users", i.e. those who have at least 10 followers, who follow at least 10 others, and have tweeted more than 10 times.
Twitter users are undoubtedly becoming more active, according to the report, but the number of new sign-ups has been declining since a time that Barracuda Labs refers to as Twitter's "red carpet era".
The report explained that many celebrities had opened Twitter accounts between November 2008 and April 2009, causing the site's popularity to surge.
"It was during this time that 27 of the top 50 and 48 of the top 100 most-followed Twitter users joined and began tweeting and promoting the service on a daily basis," the report said.
"With the increased visibility of Twitter, the millions of fans of many of these celebrities also joined Twitter, causing the growth rate to spike."
The report comes as Twitter today announced it is to start scanning all tweets in a bid to identify links to sites which may cause harm to users.
Small Texas cable firm alleges foul play
Facebook will join fores with UK NGOs to tackle hate speech on the social network
A survey of local authorities has found that they face challenges in the areas of data, compliance and mobility.
More than 800,000 home users could be affected