There’s no arguing that social networking websites like MySpace.com, myYearbook.com and Facebook.com are more popular than ever. Yet, many people don’t seem to realize that these Web 2.0 sites can pose some online identity theft and other Internet privacy issues — not only for young people, but also for parents and guardians alike.

A few weeks ago I watched as my 14-year-old niece spent most of her free time interacting with her posse of friends on Facebook. She would occasionally come up for air to make a quick phone call or check the score of a basketball game on TV, but it was very clear to me that online security wasn’t much of a concern for her – her username was her nickname and her password, the name of a local school.

Resisting the temptation to give her a lecture about security and privacy on social networking sites (and risk losing the coveted title of “coolest uncle”) it still makes me worry a little.

Her biggest Internet privacy concern wasn’t about anyone in Facebook causing her harm, but more about her parents or younger sister getting access to her Facebook page and her rantings. Once logged in to the sanctuary of her personal page all security concerns were cast to the wind.

Maybe I should have that private chat with her father instead. I’d still have to ultimately give up that “cool uncle” trophy, but … The trouble is, whenever you have tens of millions of users gathered at single online chat frenzies, you’re going to attract a lot of unwanted attention. And I’m here to tell you that that’s a whole lot worse that being nagged by a nosey parent or guardian.

While most Web 2.0 sites spend plenty of time and money protecting their members, it’s not an exact science. MySpace, for example has suffered from a number of attacks — ranging from advertising banners infected with information-stealing Trojans, to identity stealing phishing sites, all made up to look like real MySpace pages. Other potential traps include Quicktime movies and even MP3 files, many of which are loaded with malicious code, and they act as fast and effective online ID-stealing devices.

And last year, SecondLife.com was hit with a data breach so serious, that the company instantly cancelled all user passwords. What makes SecondLife a little more tempting to identity thieves is that SecondLife focuses largely on buying and selling stuff. In addition to having the personal information on file, most users have their credit card numbers there as well.

And Facebook is not immune either. Security experts have questioned Facebook’s policy of allowing thousands of third party developers to create and sell their own applications to Facebook users. The trouble is, as a user, you can’t be certain that applications you purchase through Facebook are safe and secure.

Online thieves are also focusing on gathering enough information from MySpace and Facebook pages so that they can eventually patch the information together and create a “real identity.” Users often give away so much personal information on the Internet just by being careless that they make it far too easy for thieves. Identity theives can gather enough information on a particular Web 2.0 user to open an account under his/her name or apply for a loan.

Online users — especially teenage ones — need to wake up to the reality that social networking is not always a safe sanctuary. And as long as young online users continue to believe that their passwords and identities can’t be compromised, they’ll continue to be attractive targets for nosey parents, would-be cool uncles, and last but not least — a target for enterprising identity thieves.