New research suggests that podcasting is enjoying yet another surge in popularity and profitably these days, primarily due to improving mobile and in-car technology that makes it easier than ever to find the stuff you like. One recent poll by Edison research says that the typical podcast listener now averages six shows per week and tends to be fiercely loyal. That's led to healthy advertising models and an influx of new talent.

The surge is showing up on the charts, too. High-profile new podcasts are finding big audiences quickly, and established shows are expanding. Here are five new and returning series to add to your queue.

REVISIONIST HISTORY

Author Malcolm Gladwell has been in the mind-blowing business for several years now with best-selling books like "Outliers" and "The Tipping Point." His new limited-run 10-episode podcast series, "Revisionist History," represents one of the best debuts in the history of the medium. Each episode takes a sideways vector into a particular historical topic. "Because sometimes the past deserves a second chance," as the show's official motto reads.

Gladwell sure knows how to tell a story. The episodes posted so far have a clarity of language and structure that Gladwell fans will recognize, and it turns out he's a pretty great audio narrator, too. Episode 2 — "Saigon, 1965" — tells an amazing story from the Vietnam War and draws compelling parallels to our current conflicts abroad. It's flat-out fascinating stuff, with top-notch audio production and original music. Highly recommended.

Info: revisionisthistory.com

UNSOLVED MURDERS: TRUE CRIME STORIES

True crime is among the emerging genres proving to be especially popular in the podcasting world. The medium's first mainstream breakout hit "Serial" was classic true crime storytelling, and the podcast "Criminal" regularly does brilliant things with the concept.

Another new podcast just a few episodes in, "Unsolved Murders: True Crime Stories" goes in another direction. The show takes a sort of old-timey radio approach, employing a cast of voice actors to stage dramatic recreations of "unconventional cold cases and mysterious deaths." There's an element of B-movie camp to the proceedings, which might not be to everyone's taste, but the show so far has a pleasant, PG-13 ghoulishness.

Info: parcast.com/unsolved

INVISIBILIA

NPR's popular program "Invisibilia" returned for its second season on June 17, with new co-host Hanna Rosin and a fresh slate of intriguing topics. The show has a unique topical mandate: to explore the invisible forces that shape human behavior. The producers always manage to find interesting riffs on the theme.

To wit, check out the debut episode "The New Norm," which delves into two genuinely strange stories concerning oil rigs, EST seminars, McDonald's franchises and Russian cultural psychology. New episodes drop on Fridays and the team is planning only seven episodes in the Season 2 run, so now's the time to get on board.

Info: npr.org/programs/invisibilia

AMERICAN MASTERS PODCAST

The long-running PBS series "American Masters" recently launched a digital archive service that will provide online access to more than 800 interviews and 1,300 hours of culture vulture awesomeness. It's a deep and valuable treasure trove of biographies and profiles on America's greatest writers, artists and performers.

Along with the digital video archives, PBS is launching the "American Masters Podcast," which will feature long-form interviews from the series 30-plus years of documentary films. The first season of the new series presents interviews with influential women discussing powerful female voices in the culture. Gloria Steinem examines the life and career of Marilyn Monroe in the premiere. Future episodes in the queue: Carol Burnett, Lena Horne and Billie Jean King.

Info: pbs.org/wnet/americanmasters

STUFF THEY DON'T WANT YOU TO KNOW

Originally a spinoff of the elder statesman podcast "Stuff You Should Know," this conspiracy-minded program has the benefit of exploring topics that are inherently interesting. Besides the conspiracy theory business, the podcast ventures into areas like paranormal phenomenon, corporate intrigue, world mythology, cryptozoology, cults and, of course, UFOs.

Hosts Ben Bowlin and Matt Frederick have an easy chemistry, but the show can occasionally get too loose and chatty. That's always a tricky balance in this style of podcasting. The modern attention span being what it is, indulgent riffing on the mic is risky. Twenty thousand other podcasts are just a click away.

Info: stufftheydontwantyoutoknow.com