Have people actually met/seen others using Snapchat? I'm in college so tons of my friends use Snapchat regularly (about every couple of hours). Snapchat is essentially used for picture messaging of frivolous images, almost like a picture-status-update of something funny or current. Nobody I know really uses it for "dirty" pics, though unflattering pics (of yourself or others) are fairly common. It's almost a foil to Instagram - Instagram encourages you to post by making your photos permanent but beautiful; Snapchat encourages you to post by making your funny/ridiculous/unflattering photos ephemeral. See the difference? It's ephemeral vs permanent, funny/ridiculous vs beautiful.
Has any of your friends run into the problem of the expected privacy of their photos being compromised and the photos reposted elsewhere?
Boy, being an investor must be hard.
I'm not a user of snapchat, but to my college age cousins, the value isn't in "sexting", though that happens, it's in the intimate, momentary connection.
This is the same reason, for aesthetic reasons, why I prefer not to take pictures of famous buildings & landscapes. I know I was there .. it's imprinted in my mind and I can go back and explore that experience with my imagination. I don't only visualize, but I smell, I hear, I feel what it was like.
Snapchat captures that zeitgeist, whether the experiences was funny, intimate, sexy, embarrassing, cool, awe-inspiring or sad. It then goes into history, save the shared mindspace of 2.
That's something people want.