NEW YORK - "ILY!" Susan Maushart's 16-year-old daughter often calls out over her shoulder as she leaves the house. Sure, actual words would be better. But Mom knows not to complain.

"A mother of teenagers is pathetically grateful for an 'I love you' no matter what form it takes," she observes.

Then there are the various forms of "LOL" that her teens use in regular parlance - it's become a conjugable verb by now. And of course, there's the saltier acronym used by son Bill: "WTF, Mom?!" But before you judge, note that former VP candidate Sarah Palin just used that one in a TV interview. And CNN's Anderson Cooper used it on his show the other night.

Acronyms have been around for years. But with the advent of text and Twitter-language, it certainly feels like we're speaking in groups of capital letters a lot more. It's a question that intrigues linguists and other language aficionados - even though they'll tell you they have absolutely no concrete research on it.

"It's fascinating," says Scott Kiesling, a socio-linguist and professor at the University of Pittsburgh. "What's interesting to me as a linguist is figuring out which words get picked up, and why. What is it that makes OMG and WTF and LOL so useful that they spread from the written to the spoken form?"

One possibility, Kiesling proposes, is that some of these acronyms actually become a whole new thought, expressing something different than the words that form them. For example: "You wouldn't say, 'OMG, that person just jumped off a cliff,'" he explains. "But you'd say, 'OMG, do you see those red pants that person is wearing?'"

Which brings us to WTF, an acronym that needs no translation. When Palin used the expression recently in a Fox News interview - twice in two sentences, actually - some pundits were a little shocked. (Palin was playing on the president's "Win the Future" message in his State of the Union speech.)

"That's going to be a tough one for her to come back from and explain," remarked conservative commentator Pat Buchanan on MSNBC's "Morning Joe." Host Joe Scarborough simply shook his head and said: "Not very presidential."

But the chatter died down quickly. "I haven't seen any big blowup," says Kathleen Hall Jamieson, director of the Annenberg Public Policy Center at the University of Pennsylvania and an expert on political communication. "It was misplaced humor. But I assume she thought it was clever and thus would not be judged."

Clever may be in the eyes of the beholder. But Palin is not the only prominent person to use the expression on TV recently. On "Anderson Cooper 360" Monday night, the host was commenting on rapper B.O.B.'s use of an airplane's public address system to perform for the captive passengers. "WTF, B.O.B.?" Cooper asked.

Imagine if he'd said the actual words - a quick call from network executives might have ensued. But WTF seems to have become a winking way of saying something with a little edge, a little bite, without being truly offensive.

It can also be a good icebreaker with an audience. "I do a lot of public speaking," says Maushart, the mother of three, who is also an author (The recent "Winter of our Disconnect.") "And if there is one utterance that I always know will get a laugh, it is WTF. It establishes that you are kind of with it. It brings an instant laugh."

And so she doesn't mind when her kids (they are 20, 17 and 16) use it. If only she could keep up with all their other acronyms. They've graduated from the simple LOL and LOLOL to LMAO - literally, laughing so hard that part of your body comes off (for extra credit, use LMAOOTF - it means it's all happening on the floor.)

Her youngest, Sussy, 16, seems particularly advanced. These days, she has started saying "K-Dot." Translation: OK, but with a finality to it, as in, end of discussion, "K'' followed by a period, ergo: "K-Dot."

Not avant-garde enough for you? Try this: Sussy also is known to SPEAK a question mark when asking a question. As in: "Do you really want me to do that, question mark?"

All this delights Robert Lane Greene, author of the upcoming book "You Are What You Speak" and a self-described linguistics nut. Greene doesn't buy in to the concern that kids are destroying our language.

"People often think the language THEY learned was perfect," he says. "But innovation is generally enriching. It's fascinating, if you don't pull your hair out over it."

So just how new is the use of acronyms? Did this all come from Internet speak, texting and the like? "Americans have always liked abbreviations," says linguistics professor and author Deborah Tannen, author of several popular books on language. "That certainly predates the Internet."

In fact, acronyms date back to ancient times, Greene points out - the Romans and the Greeks used them. In the United States, they came into prominence in the early 20th century with the New Deal, the series of economic programs passed during the first term of Franklin D. Roosevelt - who, of course, became known by his three initials. They are widely used in the military and today's government bureaucracy.

People who think acronyms are new may be suffering from what linguists call a "recency illusion" - the illusion that something is new merely because one has just noticed it. They may not realize, for example, that the oft-used "snafu," in its cruder, more popular version, contains the same "F'' that "WTF" does.

But one thing that does seem genuinely new, Greene says, "is that these three-letter phrases from the Internet and twitter-speak are being spoken out loud."

And so, maybe you CAN blame the kids for that.

However, Greene notes, "People have been complaining about what the kids are doing to the language since ancient times, and Latin. Language is always changing. It's a fact of life."

And besides, young people are always on a search for the next new thing. And so this whole spoken-acronym thing may be a fad, destined for the linguistic garbage heap in a matter of a few years.

Remember the word "groovy"?

"One generation's teenage slang," Greene says, "is the next generation's "OMG Dad, I can't believe you said 'groovy.'"