Late last week, Om Malik of Gigaom reported that Snapchat, the self-destructing-photo app based in Los Angeles, was in talks with investors to raise a Series B investment round of $100 million, which, despite the fact that the company has no revenue, would value Snapchat at about half a billion dollars. 

A couple of days later, TechCrunch reported that the half-billion dollar valuation was a ridiculous sum...because it was too low.

"Several sources have told us Snapchat co-founders Evan Spiegel and Bobby Murphy are shooting for an even more ambitious valuation near $1 billion," it reported.  

In an attempt to explain the 10-digit valuation, there have been two charts that have been widely circulated. They are both taken from the report compiled by Mary Meeker, the Kleiner Perkins partner known for her annual Internet Trends paper. 

This is the first, which shows how insanely active Snapchat users are:

And this is the second, which contextualizes how many photos Snapchat users share, compared with Facebook, Instagram, and Flickr. 

One chart that doesn't seem to exist is Snapchat's user growth--and that's important.

When you look at the first chart, titled, "Short-term Sharing Exploding," it's easy to think that more and more people are using the app. In fact, some articles, like this one, made the claim that "More People Share Photos on Snapchat than Instagram."

But that's not necessarily accurate. And it's a semantic error with real consequence. If you read it carefully, the chart simply implies that more photos are being shared--not that more people using the app. 

While Snapchat's founders are quick to offer statistics about the number of photos shared--which is approaching a mind-boggling 150 million daily Snaps--there's notably less talk about the number of users. And that's probably because those data points are not as impressive. 

According to VentureBeat, at last count in April Snapchat had about five million users. When Facebook acquired Instagram for $1 billion, it had about six times that. 

Tech giants such as Facebook, Google, and Yahoo are willing to pay billion-dollar sums for companies with little or no revenue, so who's to say Snapchat wouldn't be "worth" a billion dollars? Markets are set by what buyers are willing to pay, and Facebook's 2012 acquisition of Instagram made it clear that, for better or worse, revenue takes a back seat to popularity. But it's important not to confuse virality among a concentrated group with mainstream popularity.

One of the biggest criticisms against Snapchat is that the site's usage is pretty much dominated by the 13-to-25-year-old demographic. That criticism often gets couched in the complaint that Snaphat's primary utility is to send lewd or sexually suggestive photos to friends (or in the less mature nomenclature of my peers, "dick pics").

Regardless of whether that's true, from a business development perspective, the complaint shouldn't be so much judged by the content of photos being shared--but it should be by the lack of diversity among its users, and the difficulty the company will have in achieving a mainstream following. 

From the company's own marketing material, it's clear that the founders are trying attract a more diversified user base. Check out this recent promotional video, which features more than one aging grandparent, and a pair of baby-boomers awkwardly explaining how they send each other "really interesting" pictures. The company is maturing, and in creating a video like this, it's trying to distance itself from the much-joked-about image as an app that's used primarily for sexting. 

"Snapchat captures the human experience," the narrator of the video explains. "Life is a series of moments and memories that happen and then disappear. Fleeting Snapchat moments are so magical and vibrant. So much like life."

It's a good strategy--probably an essential strategy--but only time and execution will tell if it will work. If Snapchat's founders really want to achieve their desired $1 billion price tag, then it's going to take a big push to expand the user base.