Leibowitz: There is no over-arching privacy statute in the U.S. He say they take a two-pronged approach on privacy, including enforcement and policy.

FORBES: FTC Chairman Jon Leibowitz: Live At D10

The Act requires operators of commercial web sites and online services, including mobile apps, who collect personally identifiable information about Californians to conspicuously post a privacy policy.

ENGADGET: New privacy policy standards agreed to by world's major app store owners

Separately on Wednesday, 36 attorneys general, including California's Ms. Harris, sent an open letter to Google protesting its new privacy policy, set to take effect in March.

WSJ: Apple, Google, Others Agree to App Privacy Rules

Most recently, critics, including some federal regulators and U.S. Congress members, objected to a revamped Google privacy policy that pulls user-activity data from the company's multiple products together to create a single user profile.

CNN: Poll: Google more popular than Apple, Facebook