Twitter has arrived. How do we know? It's been hacked like all the other hot social networks before it. (Read: Facebook and MySpace.) The cyber attacks say as much about the growing popularity of the "microblogging" site (messages can't be longer than 140 characters) as they do about the company's inability to secure its users' information. Hackers don't tend to waste their time breaking into obscure sites or writing viruses for software that no one uses.

Twitter.com on Monday revealed that cyber thugs had broken into 33 of its customer accounts, including those of  President-elect Barack Obama, pop singer Britney Spears, CNN correspondent Rick Sanchez and Fox News. Online pranksters used their access to Sanchez's account, for example, to post messages such as "i am high on crack right now might not be coming to work today," while Fox News' Twitter update reported "Breaking: Bill O Riley [sic] is gay," referring to the network's volatile conservative talk show host, ComputerWorld reported.

More than half of teens on MySpace discuss or post images on their profiles of sex, drugs and violence, new research shows. But another study finds that reminding kids the info is public may tame the content they publish on the social-networking site.

Some 270 (54 percent) of 500 MySpace profiles referenced risky behavior, according to the first study in today's Archives of Pediatrics & Adolescent Medicine. Of those, 24 percent mentioned sex, 41 percent drugs and 14 percent violence. The findings are based on reviews by researchers at the University of Washington in Seattle and the University of Notre Dame of profiles whose users said they were 18.

The researchers acknowledge that there's no way of verifying the ages or information of the users. But they note that social-networking sites have been used by cyber-bullies and online predators to target unwitting users. And whether or not the profiles reflect the truth, other teens will take the online information literally, magnifying the peer pressure that already exists in real life, says co-author Megan Moreno, now an assistant professor of pediatrics at the University of Wisconsin–Madison.

A friend I’ve been trying to convince to join Facebook forwarded me a LiveScience story this afternoon about a study that found that a person’s narcissism can be predicted by how he or she uses the popular social networking site.

In the study, which appears in the October issue of Personality and Social Psychology Bulletin, 129 Facebook users participated in a survey designed to pick up narcissistic personality traits. Another group of college kids then examined the 129 users’ Facebook pages for evidence of such narcissism.

The findings, in a nutshell: The more info that users (or their friends) posted about themselves, the more narcissistic they were deemed to be. They were also the ones most likely to have sexier and more self-promoting main profile photos.

Imagine taking the social experience of a site like Facebook or MySpace and integrating it into a Web browser so that collaboration and communication with friends and colleagues is completely seamless.

Adaptive Path, a Web design company, in partnership with the people at Mozilla Labs (a virtual lab connected to the Mozilla Foundation, the Firefox browser creators), want to do just that. In this video, they show one possible future scenario of the Web: Aurora.