An energy has taken hold in the city of Atlanta, driven by young, college-educated professionals who want -- and can afford -- a lifestyle rich in variety, diversity and excitement, all close to home. They are moving in by the thousands, transforming abandoned warehouses into lofts, vacant lots into dog parks and communities long in decline into neighborhoods of choice.

In fact, Atlanta is on the leading edge of a national trend: Since 2000, neighborhoods within three miles of downtown Atlanta have seen a 61 percent surge in residents aged 25 to 34 who have at least a four-year degree, according to U.S. Census figures. That's almost 10,000 new patrons for everything from apartment and condo developments to restaurants and bars to computer and cell phone vendors.

The same thing has happened in dozens of other cities, but the movement is twice as robust in Atlanta as it is nationwide.

Krista Ruggles and her husband moved to Castleberry Hill two years ago so he could live closer to his job at CNN. Fifteen years ago the area was full of empty warehouses and crime. Inroads by artists helped raise up the community, as they opened galleries and studios. Developers followed, renovating the warehouses into lofts.

Now Ruggles, 37, is president of the Castleberry Hill Neighborhood Association. She's proud of the changes, especially the dog park on Peters Street that draws neighbors after work and on the weekend.

"It's a true neighborhood," Ruggles said. "The dog park has its own Facebook page."

Chances are, you've encountered the phenomenon -- in the adult kickball teams playing in Piedmont Park, or conversations about whether Glenwood Park or Cabbagetown is the cooler place to live. Or perhaps you’ve walked into a pub on a night when it was packed with enthusiasts of a darts league or a trivia contest.

"The city is just getting younger," said A.J. Robinson, president of Central Atlanta Progress, a nonprofit business advocacy organization. "This is not the old Atlanta. It's much more diverse and mixed, culturally and racially."

For Ruggles and her peers it's clearly all about the urban vibe; the rest of the 28-county Atlanta metro region saw just a 7 percent increase in young, educated residents during the last decade, according to a recent report by the urban leadership group CEOs for Cities.

The rebirth of close-in communities is good for the city and the entire metro region, experts say. These young adults bring a new vibrancy to a city that is a major economic engine for the state, said Joe Cortright, senior research adviser for CEOs for Cities.

"If you have them, you attract employers and grow your economy," Cortright said. "If you are attracting them, it's usually a sign that your community is getting stronger."

Atlanta needs some good census news. The 2010 count showed that the city did not have the overall population growth that had been projected, with most of the region's growth occurring in the suburbs. And that's on top of Atlanta's recent battles with foreclosures, bankruptcies and shuttered businesses.

But there’s another, less positive term for what is happening in the in-town communities: gentrification. Even as new construction and renovations boost the city’s property tax rolls, they often constrict the availability of low- to moderate-income housing and displace longtime residents.

“Whether that is a good or bad thing depends on where you stand,” said Harvey Newman, an urban policy professor at the Andrew Young School at Georgia State University. "I guess the Starbucks people are happy."

The changes can be seen in communities such as Cabbagetown, a former factory enclave, said Newman, who served on the city's urban design commission for much of the 1990s. It evolved from an impoverished, overlooked neighborhood to a nexus for renovated lofts, coffee houses and restaurants.

East Atlanta has seen a similar renaissance. Some areas that were depressed in the early '90s have seen residential and commercial growth.

Just west of Midtown, apartment complexes have emerged that are filled with young people. In one, at 935 Marietta St., young professionals pay about $850 a month for a studio apartment in a place that has a swimming pool and resident brunches once a month -- all within walking distance of pubs, eateries and shops.

Chrissy Wild, 28, who lives near Piedmont Park, spent Friday evening at an art walk in Castleberry Hill.

"There's always something to do on a Friday night, other than just go to a bar or restaurant," Wild said.

Still, she does not expect to make Atlanta her long-term home.

That's the big question down the road: Will these young people settle in the city or move off to raise kids in the suburbs, as generations before them have done?

If they stay and their numbers continue to grow, they could change the city's direction even more profoundly, demanding more mass transit and bicycle paths, and electing younger candidates to city offices.

Wait a minute. How old is Mayor Kasim Reed again? Oh yes, just 41.