As many as one in every 500 web addresses posted on Twitter lead to
sites hosting malware, according to researchers at Kaspersky Labs who
have deployed a tool that examines URLs circulating in tweets.
The spread of malware is aided by the popular use of shortened URLs
on Twitter, which generally hide the real website address from users
before they click on a link, preventing them from self-filtering links
that appear to be dodgy. Read the full story [Wired/Kim Zetter] Also see this report [CNet/Elinor Mills]