By now, plenty of traditional media companies have hopped on the social media bandwagon, pumping out news updates on Facebook and Twitter.
But do those companies have the time and resources to work yet another Web outlet into their daily routine?
Mark Coatney certainly hopes so. Mr. Coatney, a 43-year-old journalist, is the latest hire at Tumblr, a fast-growing blogging service based in New York that says it has 6.6 million users.
Until last month, Mr. Coatney was a senior editor at Newsweek, where as a side project he headed up the magazine's social efforts on Twitter and Facebook. Last year he decided to add Tumblr to his repertoire.
"I saw it as an opportunity to talk to our audience in a new way," he said. On Twitter, he said, "the main feedback comes mostly from retweeting," or retransmitting an interesting message. On Tumblr, "the tone is a lot more conversational."
Mr. Coatney quickly cultivated a following on Tumblr for his thought-provoking, quick-witted posts. Often they included commentary that was funny and bordering on acerbic -- something he was able to get away with largely because "no one at Newsweek really knew what I was doing," he said.
The credibility he established among Tumblr users, and the fact that Newsweek was one of the first big publishers to sign on, cemented Tumblr's decision to hire him, company executives said.
Over the last few months, other media outlets have caught wind of Tumblr, which is free to use. The newest recruits include The Atlantic, Rolling Stone, BlackBook Media Corporation, National Public Radio, The Paris Review, The Huffington Post, Life magazine and The New York Times.
But many of those outlets have done little more than set up a placeholder page. In his new job as a "media evangelist," Mr. Coatney's role, and in some ways his challenge, is to help them figure out what to do next.
Mr. Coatney describes Tumblr as "a space in between Twitter and Facebook." The site allows users to upload images, videos, audio clips and quotes to their pages, in addition to bursts of text.
As on Twitter, users can follow other users, whose posts appear in a chronological stream on a central home page known as the dashboard. Users can indicate that they like an item by clicking on a red heart next to it or "reblogging" it.
One of the big differences between Tumblr and Twitter is that Tumblr does not display how many followers a user has, said David Karp, Tumblr's 24-year-old founder and chief executive.
"Who is following you isn't that important," he said. "It's not about getting to the 10,000-follower count. It's less about broadcasting to an audience and more about communicating with a community."
Moreover, he said, the site was designed with creative expression in mind.
"People are creating identities and personalities that Facebook and Twitter are not designed to allow you to do," he said.
Since Tumblr is currying favor among a young crowd, it could prove valuable for traditional companies and media outlets that are trying to build a relationship with that audience. And those companies are no doubt aiming to win points by being early adopters of a site that is on the rise.
Tumblr is still dwarfed by Facebook and Twitter, which each have hundreds of millions of users and can be significant sources of traffic for online publishers.
Mr. Coatney estimated that posting links and notes to the Newsweek Twitter feed and Facebook page sent roughly 200,000 to 300,000 readers to Newsweek's Web site each day. By comparison, Tumblr sent closer to 1,000.
But Tumblr is growing quickly. It says it is adding 25,000 new accounts daily, and each month it serves up 1.5 billion page views.
Items posted on Tumblr can also ripple out to far-flung corners of the Web.
When The New Yorker posted the Escher-inspired oil-spill-themed cover for its July 5 issue on its Tumblr page, it drew many links from other sites.
Alexa Cassanos, director of public relations for The New Yorker, which began using the service in late May, said the cover resonated in unlikely places, like the news aggregator Reddit.
Ms. Cassanos said Tumblr afforded The New Yorker an opportunity to showcase some material that might otherwise get lost online.
"We can highlight graphic content like photo essays or slide shows to an audience that may not read the magazine," she said. "You just couldn't do that, visually, on Twitter or Facebook."
Unlike Twitter, where it is not uncommon for publishers to simply set up accounts that automatically publish links to their articles and blog posts, Tumblr requires publishers to add more commentary and interaction if they want to win favor with its community.
Mr. Coatney acknowledged that this might not be an easy sell, particularly when the payoff was not immediately obvious.
"It's a huge leap of faith for many of them," he said. "Monetizing that relationship is still a difficult hurdle because you may not be getting new readers at that particular moment, even if you are engaging with them."
For publishers, services like Tumblr reflect a broader shift in their relationship with their audience, said James E. Katz, a professor of communications at Rutgers University.
"Going back 20 years, publications like Rolling Stone didn't interact with readers except for letters to the editor," Mr. Katz said. "One of the realizations that cultural leaders and publishers have had is that there is a lot of expertise, wisdom and ideas in their readership."
The ability to respond online turns readers into co-creators, he said, which can give them a sense of ownership.
"That is an extremely valuable commodity for publishers these days, even if it does not yet translate to revenue," Mr. Katz said.
For Tumblr, which is fleshing out its business model and recently raised a $5 million round of venture financing from Spark Capital and Union Square Ventures, the interest from media outlets is something of a feather in its cap.
"There is certainly some validation in it," said John Maloney, president of Tumblr. "They've decided that this is the next social media platform they want to adopt, and that certainly can translate into a catalyst for us."