I just text messaged to say ILU.

More and more tech-savvy lovebirds are sending sweet nothings to each other in the form of text messages via their cell phone keypads.

The high-tech dating trend, which is already huge in Japan and Great Britain where text messaging is a lot cheaper than a cell phone call, is catching on among young romance-seekers in the United States.

"[It's] a digital Post-it note that says 'I love you' or 'You're cute' or 'I'm thinking about you,'" said Xeni Jardin, a contributing writer for Wired magazine and technology correspondent for National Public Radio.

With a 160-character limit, the short and sweet text messages are inherently brief, encouraging the sender to use abbreviations — ILU for I love you — and emoticons — typed symbols of expressions.

"It's kind of like giving in to a little whim," said Stephanie Gatton, a 27-year-old grad student in San Diego who occasionally text messages an Irish man she dated while traveling in Europe. "If I'm in the moment and I'm thinking of him, I can communicate with him."

But the abbreviated language of love can leave some recipients feeling unfulfilled.

"I think text messaging is good for checking to see if someone's not busy, but I prefer a real conversation," said 35-year-old Deb Murray, who found herself engaged in a texting relationship with a younger man she met at an L.A. running club.

"When we started going out, he'd text message me and I'd respond with a phone call," Murray said. "I realized pretty early on that text messaging was his preferred method."

For some, cell phone dating's biggest draw is its discretion.

Christian Detlefsen, a 27-year-old recent M.B.A. grad, said his girlfriend of eight months sends him brief under-the-radar love notes.

"It's a privacy thing," he said. "She knows I'm in a meeting and can't answer the phone or she's in a car with other people."

Text Message, Text Message Make Me a Match

The popularity of mobile flirting hasn't gone unnoticed by the online dating world.

Match.com, for example, launched Match Mobile (search) last year, which allows singles to view profiles and photos of other singles on their cell phone display screens and then send chat requests to begin flirting via text message.

"There is no longer a downtime in your romantic life," said Trish McDermott, Match.com's "vice president of romance."

The mobile service, which currently has 67,000 profiles — 69 percent male and 31 percent female — appeals to a younger demographic, according to McDermott.

"It's more of a 20-something product than a 40-something product," she said. "Mobile phone dating was for us a way to reach out to a community of single people who feel comfortable texting."

About 80 percent of Match Mobile members are 34 and under, while only 60 percent of overall Match.com members are in that age group.

Dodgeball.com (search), a mobile social-networking service that launched in April and is available in nine U.S. cities, now has a "crush list" feature.

"I think Dodgeball is going to be similar to what Friendster (search) was," said Dennis Crowley, the 27-year-old Dodgeball cofounder, referring to the popular networking site. "It didn't pitch itself as a dating site, but whenever you have a social networking service it inevitably becomes one."

For example, on Dodgeball a female subscriber creates a list of guy members who she thinks are cute. If one of them checks in with Dodgeball within 10 blocks of her, Dodgeball will send a message and a photo (if the person has a camera phone) telling the object of affection where the person crushing on him is located. At the same time, Dodgeball will text message the subscriber that someone from her "crush list" is close by.

Crowley said text messaging is a popular dating tool within his circle of friends.

"Most of my friends use it as a first stage, the flirting stage," Crowley said. "You can send a message really fast."

Don't Shoot the Messenger

But the "on a whim" immediacy can backfire.

Francine Webster, a 32-year-old Los Angeles resident, had a text messaging horror akin to a crush finding a note passed in class.

Webster was having a cross-country relationship with a New Yorker she met through work. Text messaging made the long distance seem shorter. When he was in town one evening, "we were at his hotel and drank way too much champagne," she said. And the romantic "activities" that followed were not all that she had hoped.

"Afterwards I sent my girlfriend a text message saying the experience" was lackluster, Webster said. "But I accidentally sent it to him instead. I was really embarrassed."

Across the pond, text messaging is being used as a break-up tool. Twenty percent of Britons aged 15 to 24 admitted to dumping a partner by text message, according to a recent survey.

But Jardin, the tech culture expert, said breaking up with someone is not an appropriate use for it.

"It's basically the coldest and most distant way imaginable to initiate that kind of intimate and awkward communication," she said, and added that while text messaging is a great way to test the romantic waters, it can't beat in-person love.

"It's not a substitute for face-to-face exchange."