(repurposed a prior discussion but arguably more relevant here!)
One thing I've found super interesting/impressive about Snap is that it didn't try to outcompete FB in terms of sheer network size for its usage stickiness, and instead turned smaller, tighter and more private networks into a differentiator, while at the same time providing advertisers/brands with a competitively massive audience - not an easy thing to identify, much less execute on. TBD if that differentiator is enough to keep them alive vs. FB's more traditional network-effect-driven advantage, which will be hard to beat on its own terms. I think Snap's success will depend a lot on its ability to avoid being tempted to play that game (see: Twitter!).
random other thought: this all also reminds me that Mark Zuckerberg has not made a peep about wanting FB to be thought of as a "utility" in a long time (or maybe he has and I just missed it...but couldn't find any recent mentions, see this talk from 2013: https://techcrunch.com/2013/09/18/facebook-doesnt-want-to-be...), probably in part because they are now a lot more at risk than ever before of being regulated like one. Also kind of funny to hear him talk about "we don't want FB to be cool" too, because now it seems like FB very much wants to be cool again now that Snap has become cool and has threatening user counts.