The New Haven Review has a list of 20(-ish) non-fiction writers who are under(ish) the age of 40. It's a good list with some very exciting writers, including Zadie Smith, Touré, Keith Gessen, Chuck Klosterman, and Lindy West:
West is the film editor for The Stranger, a weekly arts and culture newspaper in Seattle. She also makes a lot of noise online, both through her blog (posted on both TheStranger.com and Telegraph.co.uk) and on Twitter. On her blog, West’s bio says that she writes about “film, popular culture, lady stuff, animal attacks, and amusing garbage she finds on the ground.” Her film reviews are first-person, humorous and highly opinionated. She wrote this bit of awesomeness about Sex and the City 2. We have no idea how old she is.
Hooray for Lindy!