Facebook responds to privacy questions: Facebook responded to questions from Reps. Ed Markey (D-Mass.) and Joe Barton (R-Tex.) in a letter outlining the measure it has taken to protect minors on its network.

The social network wrote the lawmakers after being asked to explain reports that Facebook was planning on expanding its site to include users younger than 13 — something currently prohibited by the site’s guidelines in compliance with the Children’s Online Privacy Protection Act.

“At this point, we have made no final decision whether to change our current approach” to age limits, Facebook chief privacy officer Erin Egan wrote. “However we ultimately proceed, we will continue to comply with our legal obligations, including those set forth in COPPA,” she wrote.

In a statement, Barton said that he still has concerns about the possible plans and that he would like to continue discussing those plans with the network. Markey called for Congress to enact children’s privacy laws, “to ensure Facebook and other online companies do exactly what we know they can do, and what we know they should do.”

Yahoo patches security hole: Yahoo patched up its security systems Friday, sealing a hole that allowed hackers to access the credentials of over 450,000 users. The names taken were from Yahoo Voices, a contributor network that was called Associated Content before Yahoo acquired the service in 2010.

“We have taken swift action and have now fixed this vulnerability, deployed additional security measures for affected Yahoo! users, enhanced our underlying security controls and are in the process of notifying affected users,” the company said in a blog post.

DOJ holds up Verizon-cable deal: The Justice Department is holding up approval of Verizon Wireless’s $3.9 billion bid for spectrum from cable firms because of concerns that a cross-marketing deal attached to the deal will thwart competition for landline Internet service, people familiar with the review told The Washington Post.

Justice’s concern is that Verizon’s agreement to jointly market wireless and landline Internet services with Comcast, Time Warner Cable, Bright House and Cox could lead to the deterioration of Verizon Communication’s FiOs Internet service, which competes with cable Internet offerings.

Verizon Wireless has said it is confident its deal will be approved later this summer, and the FCC’s informal timeline to finish its review is in August.

Two-thirds of new mobile buyers get smartphones: According to a new report from Nielsen, two out of every three Americans who bought new mobile phones in the past three months opted for a smartphone instead of a feature phone.

As of June 2012, 54.9 percent of all mobile subscribers now own smartphones, with Android users leading Apple users by 51.8 percent to 34.3 percent. Despite the operating system lead, Apple was still the country’s leading phone manufacturer, the study said, with 34 percent of the market vs. Samsung’s 17 percent.

Research in Motion’s BlackBerry phones were in third place, with around 9 percent of the market.