If you're wondering why you can't meet with your fellow tweeters, it appears to be a case of cyber terrorism. Or at least some pretty thorough hacking.
TechCrunch.com reports that the popular social networking site has been hacked by a group claiming to be the "Iranian Cyber Army." There's no way to verify at this time if those responsible actually are Iranian.
TechCrunch.com recommends that if you share your Twitter password with other accounts, you change those passwords now.