(CNN)It's amazing what (literal) lengths some people will go to earn frequent flier miles. Take Ben Schlappig. Over his lifetime, he's accrued about four million miles. Half of those, he estimates, were earned on "mile runs" -- trips taken for the sole purpose of earning points. 

Recently, he completed a dizzying, non-stop trip (London-New York-Los Angeles-Honolulu-Los Angeles-London-Miami-London-Los Angeles-London) that would set most people's heads spinning. It took four days (three of which were spent almost completely on a plane), and he accrued 270,000 miles. 

He admits that the journey was exhausting, but ultimately worth it. 

"To put it into some kind of perspective, it's enough miles for two first-class tickets between the U.S. and Asia," he notes. 

"If I would have paid cash for them, they would have each cost me over $20,000." 

December -- which marks the last opportunity for many frequent fliers to earn enough to gain (or maintain) their elite statuses -- is mile-run season. In the past, the trick was looking for a cheap ticket that went the distance, as miles earned were calculated by, well, miles flown. This year, that is all set to change. 

"In 33 years of frequent flier programs, this is the year of the biggest changes ever," says Randy Petersen, founder of the online travel forum FlyerTalk and CEO of Frequent Flyer Services, which offers guidance to road warriors the world over. 

"Some of the world's largest frequent flier programs are going to a revenue model," he explains, noting that come this year, many programs will start awarding members based on how much they spend, not how far they fly. 
this is coming from what news outlet ?
CNN