Get the latest news alerts: at Twitter.

A roundup of the latest high-tech news from The Associated Press:

• Teens say text messaging is top messaging tool

NEW YORK — Teenagers have embraced text messaging as their main form of communication, but mobile phones are often a source of tension with parents and schools, a new survey finds.

The frequency with which teens text has overtaken every other form of interaction, including instant messaging and talking face-to-face, according to a study released Tuesday by researchers at Pew Research Center and the University of Michigan.

Three-quarters of teens now own cell phones, up from 45 percent in 2004. Of those who own cell phones, 88 percent text, up from just over half in 2006.

(

At the same time, cell phones and teens’ attachment to them are a source of conflict with parents and schools. Many parents limit cell phone use and 48 percent said they use it to monitor their kids’ whereabouts — either by using GPS technology or calling the child to check in. Not surprisingly, the parents of girls aged 12 and 13 were more likely to say they monitor cell phone use.

The limits did seem to have tangible benefits. Teens were less likely to report regretting a text they sent, or having sent sexual content by text message, if their parents placed limits on text messaging. They were also less likely to use their cell phones dangerously while driving.

Schools, the survey found, often ban cell phones from classrooms, and some from school grounds entirely, seeing them as a "disruptive force." Still, more than half of teens who own mobile phones said they have sent a text message during class, even though their school bans mobile phones.

Despite all the media attention to "sexting," only 4 percent of teens said they have sent sexually suggestive nude or nearly nude images of themselves to someone else via a text message. Teens who pay their own cell phone bills were more likely to send "sexts" than those whose parents pay for all or part of their bill.

The survey of 800 teenagers aged 12 to 17 and their parents was conducted on landlines and cell phones from June to September 2009. It was conducted by the Pew Internet and American Life Project and the University of Michigan’s Department of Communication Studies. The survey has a margin of sampling error of plus or minus 4 percentage points.

• Defense suppliers flock to expo at N.C. Marine base

CAMP LEJEUNE, N.C. — Defense contractors and military suppliers from around the world will visit North Carolina to promote the latest defense gear and technology slated for the Marine Corps.

Camp Lejeune is hosting the 2010 Marine South military exposition on Wednesday and Thursday. Held since 1993, the annual event features the latest in combat systems and weapons designed. It also previews new equipment in development.

The exposition is expected to attract thousands of military officers, soldiers and contractors from across the armed forces.

Camp Lejeune has been at the center of the war in Iraq since 2001. It has sent a steady stream of Marines to Iraq and units from the base were some of the first troops called to lead the surge into Afghanistan last year.

• Visa paying $2B for payments processor CyberSource

SAN FRANCISCO — Visa Inc. will pay $2 billion cash to buy e-commerce payment processor CyberSource Corp., the companies said Wednesday.

CyberSource’s fraud prevention technology is expected to help Visa to increase online use of the credit, debit and prepaid cards that bear its name. Visa is also aiming at the growing mobile payments market worldwide.

The purchase price of $26 per share represents a 34 percent premium over Mountain View, Calif.-based CyberSource’s closing price Tuesday.

The companies have worked together since 1999, and currently collaborate on risk models built into CyberSource’s automated fraud management. CyberSource currently plays a role in about 25 percent of all online commerce transactions in the U.S. It earned $11 million in 2009 on revenue of just over $265 million.

For 2010, the company forecast profit between $14.5 million and $15 million on revenue between $310 million and $315 million. The deal requires approval from CyberSource shareholders. Both boards have approved the deal, which is expected to close in Visa’s fourth quarter, which ends Sept. 30.