I have lately started to get unauthorised emails pretending to be from twitter as well as spammers trying to add me to their twitter page etc.
Just thought i would make you aware of the latest which initially fooled me as it looked very genuine (and i wasn't fully awake either so wasn't as diligent as usual.)
The email will say something like:
"Hi, you have 1 delayed message/s"
Then a link to click which looks like this:
"Twitter.com/account/messages/*********" (Bunch of numbers)
Clicking on the link though will take you elsewhere. In this case my Apple Mac (using Camino browser) alerted me not to open the page as:
"This web site at ********** has been reported as a malware site and has been blocked for your protection.
Malware sites try to install programs that steal private information, use your computer to attack others, or damage your system."
Further information can be found on the latest known issues here at Twitter: http://twitter.com/spam