(AP) -- Facebook is betting that one day soon, we'll all be acting like high school students - more texting and instant-messaging, at the expense of e-mail. Facebook unveiled a new messaging system Monday, and while CEO Mark Zuckerberg didn't go as far as declaring e-mail dead, he clearly sees the four-decade-old technology being eclipsed by more real-time ways of communicating.
"We don't think a modern messaging system is going to be e-mail," Zuckerberg said.
Right now, Facebook's Messages section is a lot like an e-mail inbox. The overhauled version, which will be rolled out to users by invitation in coming months, brings in cell phone texts, IM chats and e-mails from non-Facebook accounts.
All the messages stack up in one inbox, and they're organized by the person sending them rather than the type of technology they use. For those who want one, Facebook will hand out facebook.com e-mail addresses - mostly to make it easier to communicate with people who aren't on Facebook.
"If we do a good job, some people will say this is the way that the future will work," Zuckerberg said.
By making e-mail part of its communications hub, Facebook escalates its duel with Internet search leader Google Inc., which shook up online communications 6 1/2 years ago with its Gmail service. Google has said it will roll out more social networking features to counter Facebook's growing popularity, and within Gmail it already lets people chat, e-mail and make phone calls.
Yahoo, AOL and Microsoft are also working on incorporating messages from Facebook, Twitter and other social sites into their main e-mail systems.
What Facebook has that Gmail and others don't have, however, is people's real identities, plus a map of their real-life relationships and online interactions - something Facebook likes to refer to as the "social graph."
Facebook will use what it knows of these relationships to build a social inbox that not only filters out spam but messages it deems less important from strangers or overly chatty friends, and impersonal messages such as the phone bill. Those lower-priority messages will be tossed in a separate folder labeled "Other." Users can also tell Facebook to automatically block messages that don't come from friends.
To communicate with a friend, a Facebook user would click on the friend's name rather than hunt for a phone number or an e-mail address. If that friend prefers to get text messages, that's how the message will be seen. If the friend likes e-mail, e-mail it will be.
The messaging system, however, isn't e-mail. It doesn't use subject lines or "Cc" fields.
Facebook says it will store every missive sent between two people for eternity, unless they choose to delete it; the company likens it to this generation's equivalent of a box filled with years of love letters.
But love letters can sometimes get into the wrong hands. Running a communications service within a social network may increase the chances that sensitive information gets exposed. One of the most common complaints about Facebook is that some updates and photos posted on personal pages are seen by more people than accountholders intended, either because they misunderstood how to program their privacy settings or because of a security breach.
Google learned the hazards of melding e-mail with socializing earlier this year when it planted a Facebook-like service called "Buzz" into Gmail. When Buzz launched in February, it was set up in a way that caused many of its early users to inadvertently open up lists of e-mail contacts to outsiders. The ensuing privacy flap elicited an apology from Google, which also recently settled a lawsuit over the misstep.
Zuckerberg dismissed notions that the Facebook service, code-named "Project Titan," is a "Gmail killer," as portrayed in the media. At the same time, he said he thinks more people will forgo lengthy e-mail conversations in favor of shorter, more immediate chats.
That could lessen the need for people to use communications tools other than Facebook, said Altimeter Group analyst Charlene Li.
"It may not be a Gmail killer, but it could be nibbler," she predicted.
It could also nibble away at other e-mail services from Microsoft Corp., Yahoo Inc. and AOL Inc. According to comScore, Microsoft's Hotmail had nearly 362 million unique monthly users in September, the latest available figure. Yahoo mail followed with 273 million and Gmail, the fastest-growing service, with 193 million.
Google CEO Eric Schmidt welcomed Facebook's expanded role in online commmunications. "More competition is always good because competition makes the market larger," Schmidt said in a meeting with reporters at the Web 2.0 technology summit. "We are all well served by having everybody online."
With Facebook's foray into e-mail, Jonathan Zittrain, professor of law and computer science at Harvard University, said he'd like to see the company be more open in allowing users to turn to outside software to process their Facebook activities.
"We ought to be able to take our lists of friends, or our wall contents, or our photo archives easily from one service to another," he said.
So far, this is not the case. Users will have to keep an active Facebook account for the messaging service to work. If they decide to leave Facebook, they will lose the messaging service.
The first Internet e-mail system arrived in the early 1970s. Though e-mail is still a primary form of communication for older adults, recent studies suggest this is not the case for young people.
Text messaging has surpassed face-to-face contact, e-mail, phone calls and instant messaging as the primary form of communication for U.S. teens, according to a 2009 survey from the Pew Internet and American Life Project.
Facebook sees its messaging service as a way to deepen its connection with the more than 500 million users of its network. If it can persuade its vast audience to become faithful users of its e-mail service, Facebook conceivably will have more opportunities to sell advertising that caters to their likes and dislikes.
That ambition also could heighten the privacy issues surrounding Facebook as it becomes more deeply ingrained in people's lives and its computers become a treasure trove of personal information.
Privacy, to be sure, has been a thorn in 6-year-old Facebook's side since it was born in Zuckerberg's Harvard dorm room.
Jeff Chester, executive director of the Center for Digital Democracy, a privacy watchdog group, called Facebook's move into e-mail "deeply disturbing." He said that under the guise of giving users a new utility, the company "opens up another door that allows it to closely track how their members communicate."
Privacy concerns aside, Wedbush Morgan analyst Lou Kerner, who follows social media, sees the feature expanding the site's appeal.
"It's going to bring some of the remaining holdouts to the Facebook platform," Kerner said.
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