There's new information in the shooting of Trayvon Martin, the 17-year-old Florida boy who was fatally shot by George Zimmerman last month. Zimmerman told police that Martin assaulted him, and a family spokesman confirms Martin was suspended from school at the time of his death. Guest host Jacki Lyden speaks with Miami Herald reporter Frances Robles.

Best Buy must live in fear of shoppers like Ave Lising. He and a group of friends walk through the Stanford mall in Palo Alto, Calif., their cellphones clutched in their hands.

Lising visited the electronics retailer recently, shopping for a video game.

"I went to Best Buy [and] looked at the price," Lising says. "I was like, 'Ehh — I'm sure I can find this cheaper online.' "

So he whipped out his smartphone and scanned the barcode, found it cheaper and ... no sale for Best Buy.

There's a word for that kind of in-store comparison shopping: "showrooming."

Lester Wilson doesn't think of himself as a Republican or a Democrat. He's not a card-carrying Libertarian or Green, either.

The one group he does belong to is the 40 percent of Americans who identify as independents — a group now larger than any single political party, according to a recent Gallup survey.

"I like my independent status. I think voting for just one party is a betrayal of my civic duty," says the 38-year-old maintenance worker from Asheville, N.C.

For much of the past decade, journalist Rachel Maddow has hosted her own radio and TV shows. And for much of that time, the popular MSNBC host has been thinking about how the United States uses military force — and how it starts and end wars.

Maddow's new book Drift: The Unmooring of American Military Power traces how U.S. national intelligence agencies have taken over duties that were once assigned to the military, and how this shift has increased the public disconnect from the consequences of war.

The number of Tibetans who have set themselves on fire in the past year to protest Chinese rule over Tibet is now estimated to be at 30. Most have died.

And more self-immolations are likely.

For most of American history, early spring meant a feast of shad. That tradition has faded, but young chefs are trying to slip the ritual back onto plates.

The earliest Americans from from Florida to Nova Scotia caught shad by the basketful as they swam back from the sea to spawn in their home rivers. The fresh, silvery fish was most certainly a delight after winter's dreary fare. The American shad's Latin name is clue to its allure: Alosa sapadissima, or most delicious herring.

The debate over coronary bypass surgery versus stenting goes back decades.

Studies have been inconclusive, but doctors and patients have voted with their feet in favor of the less-invasive procedure — clearing clogged arteries and propping them open with tiny scaffolds called stents.

U.S. doctors do at least two stenting procedures these days for every coronary bypass operation.

The Justice Department's 'systematic concealment" of evidence that might have helped the late Sen. Ted Stevens, R-Alaska, defend himself in a corruption case will get a fresh airing Wednesday, when special prosecutor Henry Schuelke offers Senate testimony about his blistering 500-page report.

He's due to be before the Senate Judiciary Committee at 10 a.m. ET.

Home prices fell in most major metropolitan areas again in January, according to the widely watched S&P/Case-Shiller Home Price Indices report.

There are fresh fears about the infiltration of Afghan security forces by anti-government and anti-American insurgents after the discovery of 10 or 11 (depending on the media report) suicide vests inside the headquarters of that country's defense ministry and the arrest of more than a dozen soldiers.