These days, everyone wants to be Linda Cordes' friend -- and she's not sure how she feels about that.

The 55-year old Cincinnati schoolteacher has been flooded with requests from people who want to be included on her list of Facebook "friends," which has left her feeling decidedly conflicted.

"It's great that I'm hearing from people I haven't seen since I was 10," said Ms. Cordes, who signed on to the social networking site a year ago. "But there are people who want to 'friend' me who I wouldn't be friends with normally, so why would I take what little down time I have to put them on Facebook?"

To friend or not to friend: That's just one of the many vexing challenges confronting baby boomer Facebook users -- the fastest growing demographic on a site that has exploded in popularity in 2008, growing 127 percent to 222 million visitors and ranked as the top social networking site worldwide.

Facebook has not released statistics detailing the ages of those new visitors, but nearly a third of Facebook users are between the ages of 35 and 54, according to Comscore, an online audience measuring company.

Spawned in a Harvard dormitory in 2004, Facebook was once exclusively the province of college students looking for a place to hang out online, swap photos or post messages -- known in Facebook-ese as "status updates" or "writing on your wall." Now open to anyone with an e-mail address, Facebook is the social network of choice for dissident political groups in Egypt and international celebrity gossips.

Prince Harry's ex-girlfriend, Chelsy Davy, announced she'd split with him on her Facebook page. Republicans at a recent national committee function first bragged about how many guns they owned, then went on to boast about how many friends they have on Facebook.

Most noticeably, though, over-50-somethings are embracing the site -- much to the dismay of their children, who've moved on to Twitter.

"Facebook is my new CNN," says Melinda Browning, a Santa Fe interior designer, who said she found out about the demise of Domino, a shelter magazine, on Wednesday by checking a friend's status update.

"It's just wild. I started using it to keep up with my 20-something Canadian cousins and never thought it would turn into much more than that. I'm shocked at how it's blown up just in the last year."

Why the momentum, now? President Barack Obama, the first truly tech-savvy candidate, used Facebook for his campaign, sparking an apparent surge in new users this fall. But interest has been building for a while, says Chris Brogan, president of New Marketing Labs, a social media consulting group.

"There's been a real wave for about a year now," he said. "When teenagers grow up, they get off MySpace.com and move on to Facebook, unless they're musicians or comedians."

There's another factor at work fueling the migration of older people to Facebook, says Fred Stutzman, a doctoral student at the University of North Carolina at Chapel Hill, who teaches a class on Facebook.

"Showing your personal information online is so commonplace that it's no longer stigmatizing," he said. "A lot of people who sat on the sidelines until this point are not as concerned about putting information online because so many people are doing it.

"We're getting to a place where having something like a Facebook account is as normal as having e-mail or a cell phone."

Or a spy camera.

"My mother was going to rent a room to a medical student, but after she looked at the student's Facebook page of drunken debauchery, she said no way," said Sandi Svoboda, 41, a writer for Metro Weekly, an alternative newspaper in Detroit.

Older users, Mr. Stutzman added, tend to prefer Facebook to MySpace, which is garish and loud -- you can have your favorite rock song blaring when you open it -- and peppered with big fat Fox ads (the site's owned by Rupert Murdoch) "and you can spam all your friends," he added. Facebook's friendlier, more intimate template resembles those freshman facebooks you studied so intently in college, or an online scrapbook for photos and messages.

Older Facebook users, however, face issues never contemplated by college students.

What if your boss "friends" you and you don't want to be her friend? How many friends are too many? Most studies say that the friends we care about most number, on average, around 10. What does that say, then, about the person with 1,000 "friends?" (Facebook draws the line at 5,000).

Most important, what to do with the friend request from someone you haven't seen in decades? It's not a problem for an 18-year old user, but an all-too-common one for the 54-year-old on Facebook.

Is that eighth-grade boyfriend a creep? Or is his renewed acquaintance one of the sweet dividends of Facebook? Conversely, is it appropriate to "friend" someone half your age? Your teenager's friends?

"I tell my students, don't friend me on Facebook until after the semester is over," said Ms. Svoboda, who also teaches a political science class at Wayne State University and who joined Facebook last spring.

Tom Teicholz, a film producer in Los Angeles, noted that he had moments of "moral doubt" when first signing up for Facebook.

"I don't feel comfortable having my friends' teenage children be friends on my site, and I don't friend people I don't know -- a rule I just broke this morning when friended by a performer whose work I know. All of which will probably evolve further, with time," he wrote in his regular "Tommywood" column in The Jewish Journal.

For some though, the Facebook craze is overhyped -- the Citizens' Band radio of our era, an ultimately unsatisfying form of social communication that will fade as people move on to the next Internet trend.

"I hate to say this, but I actually find it to be very shallow. So much of what's written there is just loser language," said Howard Elson, a pediatric dentist and an actor who lives in Squirrel Hill. " 'Oh, so-and-so got up late,' 'I'm having cornflakes now,' that sort of thing. Maybe I'm just not getting it completely, but people are chronicling the most ridiculous things."

But for baby boomers dealing with divorce or an empty nest, Facebook is a godsend.

After Ms. Cordes' divorce a few years ago, she felt a bit lost, signing on to Facebook only "after people I admire started using it. I figured if I used common sense, it would be fine, and it is. I can reconnect with friends in China, Colorado and California -- or people down the street. Get an update from them and then move on to grading papers.

"My students use it in a totally different way," she added. "For them, Facebook is about, 'Where's the next party?' For me, it's about connecting with friends I don't have time to talk to while I'm at work, to see what's going on in their lives, and yes, to kind of feel better about myself."

Sooner or later, though, Facebook holdouts may find themselves following in the footsteps of Jeanne Marie Laskas, a freelance journalist and writing professor at the University of Pittsburgh. She resisted signing on for months because of Facebook's reputation as the online equivalent of a high school reunion.

"I've never been to those reunions," said Ms. Laskas, who declined to give her age but described herself as a boomer.

"It's not that I don't like those people, but it's too embarrassing, a whole other life. Why would I want to get on something like that? Basically, it was, 'I don't want to be bothered by all those people I'm done with.' "

Then, after "these lengthy, huge conversations" with like-minded friends about whether to go on Facebook or not -- "I was getting a headache from it all" -- she decided to take the plunge last week.

Now, Ms. Laskas is a convert -- at least for now.

"I'm thinking, wait a second! I do like a lot of people!" she said. "It's like this party you so didn't want to go to, you would have rather stayed home in your pajamas and instead you drag yourself out to this darn thing and you realize, this is great! I'm having a really good time! What was the matter with me?"