Bill Chappell

"Americans now walk the least of any industrialized nation in the world," says writer Tom Vanderbilt. To find out why that is, Vanderbilt has been exploring how towns are built, how Americans view walking — and what might be done to get them moving around on their own two feet.

Talking with Morning Edition co-host Steve Inskeep about what is wrong with Americans' relationship with walking, Vanderbilt says, "The main thing is, we're just not doing enough of it."

Days after it was acquired by Facebook for $1 billion, reports have emerged that Instagram now has more than 40 million users in its photo-sharing community. The gain, which was derived from the service's API, represents a spike of 10 million Instagram users added in the past 10 days, according to Venture Beat.

When he appeared in court on second-degree murder charges in the shooting death of teenager Trayvon Martin, George Zimmerman was accompanied by his new defense attorney, Mark O'Mara. Hours after the hearing, O'Mara told NPR that he doubts the case will go to trial in 2012.

But in the meantime, O'Mara tells Tell Me More host Michel Martin, he'd like to get his client out of jail.

George Zimmerman, who says he killed unarmed Florida teenager Trayvon Martin in self-defense, has been arrested and will face a charge of second-degree murder, says State Attorney Angela Corey, the special prosecutor investigating Martin's death.

Corey said that Zimmerman turned himself in to the authorities Wednesday.

Convicted murderer Charles Manson, sentenced to life in prison for his role in the grisly deaths of seven people in 1969, will not be released from prison, California's parole board decided Wednesday. The hearing, which Manson did not attend, may have been the 77-year-old's last chance at freedom. His next bid for a parole hearing isn't likely to be heard until 2027.

The bulk of the U.S. military force in Afghanistan is slated to leave the country by 2014. But the Pentagon is willing to keep some Americans there to train Afghan forces, according to a report by NPR's Tom Bowman.

Here's Tom's report for NPR's Newscast:

"Afghan Defense Minister Adbul Rahim Wardak says his country is looking for an enduring long-term relationship with the United States. And part of the relationship centers on training and equipping Afghan soldiers and police."

The Federal Reserve's policymakers seem to be reluctant to consider any more efforts to inject a monetary stimulus into the U.S. economy — but that doesn't mean you should expect the central bank to raise interest rates any time soon.

Iranian officials spoke out Tuesday to insist that reports that the country is killing access to the Internet are grossly exaggerated. Several news outlets had picked up on a report from Reporters Without Borders — a report that contains the information that "Iran has announced the launch of a national Internet."

Lawyers for George Zimmerman in the case of the shooting death of Trayvon Martin say they are no longer representing the man who killed the unarmed Florida teenager.

Defense attorneys Craig Sonner and Hal Uhrig announced their decision in an appearance outside the Seminole County Courthouse in Sanford, Fla.

The two lawyers said that they had fallen out of contact with Zimmerman.

Uhrig also said that he "heard today" that Zimmerman had been in direct contact with the special prosecutor in the Martin case, according to Reuters.

U.S. beach volleyball star Kerri Walsh is honing her game for the 2012 Summer Olympics in London, where she and her playing partner, Misty May-Treanor, hope to continue a streak of dominance that goes back to the 2004 games in Athens and Beijing in 2008.

Speaking with Morning Edition co-host Renee Montagne, Walsh says the duo's effort to represent the United States this summer is going well.

America's reliance on coal to produce electricity has declined by more than 20 percent in recent years — but in 2011, the U.S. exported coal at a rate not seen in 20 years, according to the AP. And much of the new surge in coal exports comes from Asia and Europe.

Here's a rough guide to who's buying America's coal, based on the AP story:

• South Korea: Up 81 percent to more than 10 million tons.
• India: Up 65 percent, to 4.5 million tons.

Anders Behring Breivik, the Norwegian man who confessed to killing 77 people last July, was not criminally insane when he bombed a government building and gunned unarmed people down at a youth conference, according to two psychiatrists appointed by a court in Norway.

The new development comes days before Behring Breivik's trial is set to begin, on April 16.

Jack Tramiel, the man behind the Commodore 64 computer, died Sunday, according to reports. Tramiel, who was 83, came to America after World War II. He was a survivor of the Auschwitz concentration camp in his native Poland.

Update: This post has been updated to reflect Tramiel's liberation from the Ahlem work camp, after his time in Auschwitz.

Facebook's decision to acquire Instagram for $1 billion set off strong reactions among Instagram users Monday, when the deal was announced. And if any users of Instagram's photo-sharing service were in love with the deal, they seemed to be keeping pretty quiet about it.

In 2012, the federal tax return deadline is Tuesday, April 17 — so if you haven't already filed your income tax return, you have about one week left to shop around for different options to finish your taxes, or request an extension.

Tax Day 2012 is looming — and after we file our returns, many of us will try to figure out what to do with the seemingly innocuous but possibly crucial documents we use to prepare our returns. Filing electronically can make those records easier to manage. But what should we really keep, and for how long?

Most experts recommend holding on to financial records for three years after they're used in a tax return — that's the amount of time the IRS has to audit taxpayers.

College basketball's Final Four men's teams will play in New Orleans Saturday, to decide which two squads will play in Monday night's NCAA championship game. The first match-up pits the University of Louisville against tournament favorite — and archrival — the University of Kentucky. In the second game, Ohio State University will face the University of Kansas.

This summer, U.S. archer Khatuna Lorig hopes to return to the Olympic Games. But she's already helped put archery into The Hunger Games this spring — by training the film's star, Jennifer Lawrence, to shoot.

In the kill-or-be-killed competition in the film drawn from Suzanne Collins' book, Lawrence's character, Katniss Everdeen, relies on her ability with a bow. And Lorig worked with the actress to ensure she had proper form.

Brazil took a step toward relaxing its strict ban on alcohol at soccer stadiums Tuesday, responding to World Cup organizers' concerns. The Federation International de Football Association is pushing for the change so it can make Budweiser the "Official Beer of the FIFA World Cup" when Brazil hosts the event in 2014.

The elite athletes who travel to London for this summer's Olympic Games will include petite gymnasts, huge wrestlers — and elite horses, which compete in dressage and other events. Getting these strong and delicate animals to the Olympics is no job for an amateur. In fact, it's the job of Tim Dutta, who owns an international horse transport company.

News that Google will place its dozens of services under one privacy policy — a change that also means the company will compile and collate each user's data from all those products — has some of its customers scrambling to restrict their privacy settings before the new policy goes into effect on March 1.

One of science fiction's jobs is to give humanity a map of where we're headed. From Jules Verne to William Gibson, sci-fi authors have described their versions of the future, and how people might live in it.

Those ideas came up in a recent conversation I had with Brian David Johnson, who works for Intel as a futurist — a title that gives him one of the tech world's cooler business cards.

The Two-Way is formally off-duty for the Presidents' Day holiday. But not only does the news not take a holiday — often, holidays are the news. Here's a quick roundup of some of today's important and most-discussed stories:

• Syria is reinforcing its military in what seems to be a bid to control Homs. (AP)

Major League Baseball's spring training has begun, as catchers and pitchers have made their way to Florida and Arizona to prepare for the 2012 season. Games in the Grapefruit League and Cactus League won't begin until early March, when all players will report to camp.

The Colbert Report is set to resume production Monday, after a hiatus last week brought on by concerns over the health of Stephen Colbert's mother, according to reports. Lorna Colbert, 91, lives in Charleston, S.C., where the Comedy Central star grew up.

Gary Carter, the former Major League Baseball catcher who helped the New York Mets win the 1986 World Series, has died of brain cancer at 57. In a career marked by tenacity — and the ability to hit homeruns — Carter was chosen for 11 All Star teams.