Twitter handles 80% of my news consumption somewhat like a "conversational RSS feed." I follow reporters and opinionators I respect and read the links they post to stories.
sorry for repeating myself, but I think they will have a much harder time and will do worse than twitter. At least with twitter you can identify an interest graph. Snapchat is similar in a sense but monetizing stories is a tough sell, because there is no real contextual information on what your friends are actually creating stories about. I just don't see people following brands on snapchat like they do on twitter. Snaps filters I will say are effective, but just how effective we'll see.
Snapchat's entire premise is based on ephemerality so even if someone were to advertise or brand, it goes away and is done. You can rewatch stories but even that is limited. Like twitter I don't see this product crossing over to a more general use of the population like facebook. Even expansion overseas will be hard because there are already major messaging platforms that have a strong foothold. Line, whatsapp, Snow ( snapchat clone), wechat and kikao. I also can't see them really expanding beyond the US.
You are forgetting how geo-targeted it is, from the filters to grouping snaps about a single event together. You can sell ads for music festivals, concerts, sports games, informal social gatherings, etc based on where it is and who is there.
surprisingly however, video as a medium has exploded recently and with the advent of 'live' and popularity of stories on instagram, Snapchat is in a good spot.