This could be an ominous sign for everyone that serves up ads on their blog, website, etc.

“Consumers who say their personal information has been sent to advertisers without their knowledge have launched a legal battle against Apple and the makers of some of its most popular apps, the latest skirmish in the fight over the boundaries of privacy online.

Two new class-action suits filed last week in U.S. District Court in California name the creators of Backflip, Dictionary.com, Pandora and the Weather Channel, among others, in addition to Apple. The suits follow attempts by federal regulators and lawmakers to set clear standards in the rapidly evolving – and often murky – world of digital data.

“We are in a world where every pixel that appeared on a screen could be under the control of a different party, and that really made everything much more complicated,” said Marty Abrams, executive director for the Centre for Information Policy Leadership, an industry-funded think tank.

One suit was brought by KamberLaw, a firm that specializes in consumer class-action suits and digital privacy, on behalf of a California resident. The second is led by Dallas lawyer Majed Nachawati of Fears Nachawati, representing consumers in Texas and California. Both accuse the companies of violating federal privacy laws, including the wiretapping act, for their financial gain.

“Users ought to have control over the amount of data that is sent of their activities,” said Jeremy R. Wilson, a lawyer with Wilson Trosclair & Lovins who is working with Nachawati on the case. “It’s an invasion of their privacy, and it’s done without their consent.

The suits said personal information at risk included users’ ages, gender and location along with a unique device identifying number, or UDID, that Apple assigns to all iPhones and iPads. The complaint mirrors the findings of an investigation published this month by the Wall Street Journal that found many of the most popular apps distributed such data to third-party advertising networks without consumers’ knowledge or consent – and at times in violation of Apple’s privacy policy.

“Consumers are engaged in a marketplace, but it’s not a fully informed market,” said Dave Stampley, a lawyer with KamberLaw. “They’re paying with their information and not realizing that.”

The only problem with with the these actions is that the technology has been used in a wide range of devices. For instance Microsoft has using UDID to track usage of it’s Windows operating system. It’s also doubtful that user information is being used without their consent. Websites – such as Macsmind – have crafted terms of service and user agreements that clearly state that use of the site constitutes permission to submit to “cookies” which – among other things – collect user info.

However, if this action is successful lawyers could well go after individual websites, as well as large media outlets which also collect user data.

Something to be concerned with and to keep your eyes on.