Remember the first time you heard about Snapchat? Sarah Epler won't soon forget.

"The best day and worst day is when someone [in the company] discovers a new social platform," says Epler, who works as the senior director of social media and fan engagement at MTV. She pantomimed the frenzy of questions from superiors and colleagues that follows the news that young people are using a new social network, such as Snapchat: "'Why aren't we on it yet?' 'What is our strategy?'"

Onstage at Social Media Week's Tuesday panel on how brands use Snapchat, Carla Zanoni, the executive editor of emerging media at The Wall Street Journal, nodded her head in understanding. Her brand, that stately century-and-a-quarter-old newspaper, launched its Snapchat Discover feed on January 6 of this year.

"It's a misunderstanding that young people aren't interested in business and markets and smart analysis," she said, explaining the Journal's decision to broadcast stories by reporters over its Snapchat Discover magazine, which puts out a new edition every weekday morning. (She did admit that young people also enjoy using Snapchat's Lenses, including a particularly popular one that allows you to appear to be "vomiting rainbows." The Wall Street Journal will not, she said, be "vomiting rainbows" anytime soon.)

The audience consisted of several hundred media buyers, ad reps, and social media marketers packed into the New York Times Center's auditorium. They were rapt as panelists discussed the difference between Snapchat Discover--where just a couple dozen media properties have magazine-like content feeds--and what most call the "brand" Snapchat, which is just like an individual's account, and can be found under "Stories."

Snapchat hasn't released user data in months, so it's actually bizarrely unclear how many people are regularly viewing snaps. The most recent numbers the company has released show 100 million daily active users, 86 percent of whom are between the ages of 13 and 34 in the United States.

In a separate panel discussion at Social Media Week on marketing over Snapchat, Dan Grossman, who leads platform partnerships at Gary Vaynerchuk's Vayner Media, speculated that there are likely 200 million active daily users on Snapchat now. He also said that more than 60 percent of 13-to-30-year-olds who have smartphones are on Snapchat regularly.

Another way to think about it? "It's this generation's TV," he said.

On the other end of the stage from Epler and Zanoni at the first panel was Aaron Wolfe, a social media specialist who runs the Snapchat presence of American Airlines. He admitted to using his personal Snapchat "like a 13-year-old girl," meaning, well, constantly snapping and broadcasting his "story" to anyone and everyone who wants to follow along. His approach to running the brand's feed is that of a digital-native social-media-junkie Millennial. And that's a challenge at an 80-year-old airline--even one that's already making other social media work for its brand (American Airlines has 25 full-time people working customer service via its @AmericanAir Twitter feed, for example). 

"It's really hard being a corporate brand, because you have that corporate voice" in social media channels, Wolfe said. On Snapchat Stories, however, he knows he needs to ditch the corporate voice in its short videos, illustrations, and images: "You have to think about what your friends are going to want to see."

Epler said MTV's Snapchat followers are quick to let the brand know when it's not doing a great job staying true to the feel of the platform: Quick, breezy, and off-the-cuff.

"Our audience will call us out, and tell us if it's too inauthentic," she said.

And that's a big challenge for social media managers, especially in legacy brands, Zanoni said. "People are really used to being able to control the message a little bit more," she said, explaining that for some brands, even the idea of authenticity is "a jump." She continued: "I imagine it's pretty difficult to convince executives to take the risk."

For its part, The New York Times attempts to keep its Story feed on Snapchat "unfiltered," according to Talya Minsberg, the Times's social strategy editor. "Something we really like to stress to our reporters is that this is a way to give our viewers unfiltered access," she said at a separate Wednesday discussion. One snap might be a short video of Hillary Clinton on the campaign trail taking a selfie with a potential voter. 

And journalists are given the keys to the account to cover specific events--even some that don't make the newspaper's pages the following day. One staffer used it to explain the concept of caucusing using pieces of popcorn. Minsberg said she recruited opinion columnist Charles Blow to do a question-and-answer session in part over Snapchat.

But then, he got into the filters.

"At one point he was, like, underwater," Minsberg said. "Which is not what you would expect from a New York Times opinion columnist."

On the other hand, he didn't get into the rainbow puke. Or at least he hasn't yet.