The torrent of opposition from users, consumer privacy advocates and even U.S. lawmakers has prompted the founder and chief executive officer of Facebook to change course and, once again, overhaul privacy controls, particularly in the social media giant’s friend-sharing strategy with third-party websites.

The Federal Trade Commission, the nation’s primary consumer protection agency, is already looking into privacy controls on Facebook, the top social network with more than 400 million users – more than a quarter of them under the FTC’s purview. But Facebook’s controversial sharing of user information with third-party sites has placed renewed pressure on the FTC to take action in the increasingly challenging and complex arena of Internet privacy.

The “rapid-fire” pace of mobile technology and the “explosion” in social media has warranted a review of an existing federal rule protecting children’s online privacy to make sure it is adequate, the Federal Trade Commission told a Senate panel today. Congress passed the Children’s Online Privacy Protection Act (COPPA) in 1998, directed at the unique privacy and safety risks associated with children under 13 accessing the Internet. The FTC’s COPPA rule took effect in 2000.

Even before a group of U.S. senators asked the Federal Trade Commission to look into Facebook’s new sharing platform with third-party sites, the agency had declared that data security and privacy have become a central focus of the agency’s consumer protection mission. FTC’s Acting Chief Privacy Officer Kellie Cosgrove Riley even held a one-day boot camp for federal officials on top legal privacy issues.

When Facebook first revealed it would share personal profile information with third-party partner sites, users and privacy advocates voiced concerns and anger. Now a U.S. Senator wants the Federal Trade Commission, the agency that protects consumers from advance-fee schemes, deceptive marketing practices and credit card scams, to consider if federal guidelines are necessary to protect social media site users from privacy violations.

The tally of exposed credit card accounts is up to 8 for Blippy, the new Twitter-like social site that has been coping with a public relations crisis and a privacy breach that caused a wave of users to ask for their accounts to be deleted over the weekend. Blippy said it could not confirm that all eight accounts were exposed in search results, but it reached out to the 8 individuals to “assist them in resolving any issue that may arise,” according to today’s update from Ashvin Kumar, Blippy co-founder and CEO.