Not so long ago, it wasn’t unusual to be gainfully employed, married, and well on your way to having your first child by age 22. (Don’t remember? Ask your parents.) Today, that life path feels like one step away from “Teen Mom” compared to the slow, meandering trail that many 20-somethings are blazing. The average man and woman are 27 and 26 when they tie the knot now, compared to 24 and 22 in 1980. And 80 percent of 2009 college grads moved back in with Mom and Dad after the cap-and-gown ceremony, compared to 67 percent just three years ago. (It’s called a “rent savings plan.” All the cool kids are doing it.)

What’s more, even the laws that affect what 18-and-overs can and can’t do are changing. New credit card rules ban companies from issuing plastic to anyone under age 21 unless they have proof of income or a co-signer (like a parent). Health care changes have made it possible for kids to stay on their parents’ health insurance policies up to age 26. And almost every state in the U.S. has implemented some kind of graduated driver’s licensing system—in more than a dozen, drivers don’t get full privileges until at least age 18.

So here’s the chicken-and-egg question: Are laws changing because we, as a culture, are babying teens and 20-somethings into adulthood, or are we just adjusting expectations to fit a new it-takes-longer-to-grow-up reality? When do we become adults, and when should we be treated as such?

When I was 18 and in college, I got plenty of credit card offers. I even got a couple of credit cards. And I didn’t use them wisely at all. Last year, the average college undergrad had more than $3,000 in credit card debt on an average of more than four cards. Frankly, that sounds pretty adult to me—plenty of 30-somethings and over have plenty of credit card debt—but perhaps that’s not the grown-up behavior we should be pushing. Let’s hope the new credit card rules will encourage parents to be more involved in their kids’ credit behavior and help them learn to use plastic responsibly before they’re turned loose with their own $10,000 credit limit. (Shoes! Dinners out! FREE MONEY!)

And while some people feel that letting kids stay on their parents’ insurance until age 26 is a recipe for sitting-in-the-basement-playing-Guitar-Hero disaster, let’s not forget that young adults are the most uninsured age group out there. Nearly a third have no health insurance, and not because they’re being wildly irresponsible (although that may account for some of it). They don’t have coverage because they’re more likely to be working part-time jobs, employed by small businesses that don’t offer it, and unmarried. (When you’re 22 and hitched, remember, only one of you needs a health insurance plan.)

Plus, p.s., have you seen the job market, lately? Last time I checked, they weren’t passing out paychecks at the local mall, and some 20-somethings just can’t find work. In fact, a survey from last October found that one out of 10 adults ages 18 to 34 say they’ve moved back in with their parents because of the poor economy. (Fabulous setup or a necessary evil? Bundle readers weighed in here a couple months back.)

Allowing kids to ride on their parents’ insurance coattails for a while isn’t treating them like non-adults—it’s an acknowledgement of a challenging economy. It’s also a tip of the hat to the fact that 20-somethings aren’t going straight from college to 9-to-5 anymore. (Don’t pass “Go.” Collect $50,000 in student loans.) Today’s 20-something crew may well end up being “the most educated generation in American history,” according to a recent Pew Research Center report—partially because they’re hitting up grad school due to the lack of jobs.

But there’s another aspect to this trend. We’re not just tweaking laws: We might be changing what it means to grow up. There are some experts who feel that these trends are part of a new life stage—a kind of extended adolescence that stretches from age 18 to the late 20s. Jeffrey Jensen Arnett, a research professor in the psych department at Clark University in Massachusetts, calls it “emerging adulthood.”

“People don’t go from adolescence to young adulthood at 18, 19, 20 as they did 50 years ago,” Arnett says. “It doesn’t happen until close to age 30 for most people now.” Arnett thinks that changes in expectations and opportunities have made it possible for 20-somethings to explore their opportunities in ways that previous generations couldn’t—and that it’s not such a bad thing. “Most 20-somethings thrive on it,” he says. “They feel good about their lives and they’re excited about the possibilities and they revel in their freedom.”

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And 20-somethings may be exploring their opportunities because of another cog in this taking-an-extra-decade-to-grow-up wheel: parents. Millennials have come of age with parents who were (shall we say) more involved than those of previous generations. “One of the things I have to work with my clients on is getting them to stop calling their parents multiple times a day and consulting them for every decision that they make,” says Christine Hassler, a life coach and author of 20 Something Manifesto: Quarter-Lifers Speak Out About Who They Are, What They Want, and How to Get It. “They’re closer to their parents than any other generation, and that impacts not feeling like a grown-up, because they’re still highly parented into their twenties.”

Sarah Fulghum, the 25-year-old editor-in-chief of TotallyHer.com, agrees. “You can’t blame these people for prolonging their teenage years, when their parents make it so easy,” she says. “If society wants the 20-somethings to become adults, it all starts with their parents expecting them to be adults and holding them to that standard.”

We asked you: Have we changed our opinions of when adulthood begins? Of more than 1,200 Bundlers surveyed, 83 percent of them felt that they were expected to be an adult by the time they were 25 years old. But only about a third actually felt they’d become an adult by that age. And 43 percent feel that nowadays, people are expected to hit adulthood between ages 26 and 30.

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When I asked some 20-somethings when they’d felt like adults, some of them pinpointed an event—buying a condo, buying a car, moving out of their parents’ house. But the common themes were responsibility and independence. “I moved to LA when I was 23 and I got a dog, my own apartment, and my first decent job and started paying back my student loans,” says Crystal Bryan, 26. “I felt like maybe then I had reached adulthood.”

One survey found that only about half of Americans now view marriage or kids as adult milestones—unlike previous generations. And our Bundle survey found that “moving into your own place,” “buying a house,” and “getting a job” all topped “getting married” or “having a baby” as markers of adulthood. But according to Arnett, today’s 20-somethings are even squishier about what constitutes an adult achievement. According to him, three things come up repeatedly in studies: “Accepting responsibility for your actions, making independent decisions, and becoming financially independent,” Arnett says. “They’re not external transitions. They’re all marked by an individuals’ progress.”

In other words, adulthood now means, in the words of one of our survey respondents, “supporting yourself without having to bum off your parents.” It may also mean, in the words of another survey respondent, “when you no longer feel the need to hide the wine when your parents come to visit, even though you’ve been old enough to drink for five years.” It’s less about the wedding ring and the bassinet and more about having your own mailing address, a steady paycheck, and the ability to live your own life. And until the economy cuts these 20-somethings a break, getting from Point A to Point B takes a little longer now than it took for previous generations.

Nearly 8 out of 10 Bundlers seem to think that’s the case—that Generation Y is delaying “adulthood” more than generations before it. Is it a new life stage that’s going to stick around for future generations? Thirty years from now, will we look at 26-year-olds getting married and shake our heads, thinking, “But they’re so young!” Or is this trend merely a product of a recession and a decade of helicopter parenting? “I think that our perception of ‘grown up’ may have changed,” says Nailah Blades, a 26-year-old life coach in Los Angeles. “In previous generations it was considered grown-up to get a job, work hard, start a family and then retire. Now you have a generation who isn’t afraid to challenge the status quo.”

I’m all for challenging the status quo, as long as that means working ambitiously toward a goal of some kind. And that will become easier as the job market picks up, 20-somethings don’t have to spend so long in school, and everybody can move out of Mom and Dad’s house. I also think some of this “emerging adulthood” will inch backward as parenting becomes a little less hovercraft and a little more sideline. (See this Time article last year on the backlash against overparenting.) I definitely don’t plan to accompany my daughter to any job interviews when she’s older.

Until then, I’ll keep my eye on Generation Y—I suspect they’ll be doing some interesting things. “I think that this generation’s willingness to blaze their own path will lead to a world filled with innovative and driven people,” Blades says. “And I don’t see anything wrong with that.”

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