Fox News: Worried about your privacy online? So is a woman from Texas, who's suing Facebook and Blockbuster for posting too much information about her on the Web.

Cathryn Harris found out after the fact that Facebook added a note every time she rented a movie from Blockbuster -- a note that contained her full name and the name of the movie she was renting.

"I wasn't renting any movies that I'm ashamed of, but what if I had been? It's nobody's business," Harris told MyFoxDFW. "They need to follow the laws and respect their customers' privacy and not try to go behind the curtain."

The 25-year-old homemaker from Dallas County, Texas, said she made the discovery last year when she rented the 1985 adventure film "The Jewel of the Nile," starring Kathleen Turner, Michael Douglas and Danny DeVito. She said an alert appeared on her Facebook profile detailing the transaction.

As a result, Harris filed two lawsuits -- one against Blockbuster last year and one against Facebook last month. The suits claim a partnership between the two companies allowed Blockbuster to send Harris' movie-renting habits to Facebook without fair opportunity to opt out.

At the heart of the suit is Facebook's controversial Beacon system, essentially a tracking flag that follows you across a network of sites and reports back to Facebook on your activity. For consumers, it's a way to share more information about your daily activity; for advertisers, it's a way to learn a great deal more about an individual.

Following public outcry over the system in late 2007, Facebook CEO Mark Zuckerberg publicly apologized for the Beacon system, noting that "the problem with our initial approach of making it an opt-out system instead of opt-in was that if someone forgot to decline to share something, Beacon still went ahead and shared it with their friends."

Facebook's policy has been changed, but Harris' lawsuit alleges that whether a consumer opts in or out, Beacon is a violation of the Video Privacy Protection Act. That piece of law prevents a company from disclosing information about a customer's rental habits without their knowledge; the suit alleges that Beacon still transfers information, it just doesn't display it.

Harris initially sued Blockbuster, arguing that the company is responsible for her privacy. But Blockbuster disagrees. A spokesman for the company said "...any information we send our customers is done in accordance with all privacy laws ... a customer with a Facebook account is in control of whether they elect to keep their Facebook information private or disclose it to others."

In the meantime, the online social networking giant is settling a similar California lawsuit and has agreed to discontinue the Beacon advertising program. In response to the case, Facebook said it learned "how critical it is to provide extensive user control over how information is shared."

The outcome of the California case could determine whether Harris can move forward with a class-action lawsuit.

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