Screen Shot 2013-02-13 at 8.35.49 AMAsana is one of the only companies in the workplace collaboration space that doesn’t want to brand itself as a “Facebook for enterprise.” Which is ironic, because it’s the only one of the bunch that was actually founded by two Facebook insiders: Founder Dustin Moskovitz and Justin Rosenstein.

That distinction will be a little bit harder today, as Asana is launching a new decidedly Facebook-y feature: Hearts. It came out of a company hackathon, and it’s not quite just in time for Valentine’s day. “That would be too obvious,” jokes Rosenstein.

Feature-wise, Hearts is a lot like Likes. It’s a way to passively give positive feedback to a co-worker. It’s also a way to “vote” for things. For instance, Asana has a long internal list of features it’s working on and employees heart the ones that they think are the most important, showing a sort of “heat map” for what engineers think the company should be prioritizing. They do this with everything from potential features to what they should buy for the kitchen.

In concept, Hearts aren’t too different than Likes on Yammer and Chatter and other collaboration apps. But Asana is more around tasks, workflows, and actions than communication. So in practice, hearts are less about nodding and agreeing with what someone said, and more about validating their work or voting on a plan of action, Rosenstein says.

Likes seem frivolous but are remarkably addictive on Yammer and Chatter. Our staff has gotten so used to the reflexive way to quickly agree or nod or vote for something that we constantly wish email had a “Like” feature. Comparatively wasting the time and inbox presence to write back “Ok” or “;)” is frustrating. Hearts are worked into Asana’s inbox product for that very reason: It’s another way to register an opinion and eliminate clutter of new messages.

Ok, but why “Hearts”? Doesn’t that seem a little bit like a work place app as designed by a thirteen-year-old girl who loves unicorns? Ironically, back when Facebook was rolling its Like app out, they thought about using Hearts instead of a thumbs up and the 13-year-old-girl argument was Rosenstein’s objection at the time.

But, he says, Facebook was already a site that’s heavy on the emotion. The work place, Rosenstein argues, could use a little more emotion. “It’s easy when you are up against a deadline to miss out on all the emotional aspects of work,” he says. “We believe what a business is is a group of people who take their passions and seek to do something in the world that has never been done before. We think the next generation of software will be a very powerful way to change the nature of business.”

It’s not surprising, given that outlook, that Asana’s software is being used company-wide at big startups like Dropbox, Foursquare, Pinterest, Uber, and Stripe who are similarly mission-oriented. But it’s increasingly getting a foothold at large companies like Pearson, Harvard, and Stanford. Since announcing the premium product last year, tens of thousands of teams are using Asana, and they’ve collectively created more than 40 million tasks. The most astounding fact may be how lean Asana has stayed as its grown. It has just 37 employees, a result of obsessively insisting on only hiring A players, Moskovitz says.

A cynic (read: Paul Carr) might call Asana’s outlook of work a highly millennial one: A place where everyone gets validation and everyone is working because they’re following their passion, not simply earning a paycheck.

But roll your eyes or not, it’s this generation that are already running several major startups and will increasingly be in positions of management at larger companies. And — if the hype around enterprise software is to be believed– they’ll increasingly be creating the work place software that defines your 9 to 5.

“When we left Facebook to do this people couldn’t understand why we’d leave a company that was so cool to do something in the enterprise space,” Moskovitz says. “People see it as dull with people working in grey buildings at cubes hating their lives, but that’s not how we see it.”