YTD revenue: $538MM
Q4 should be their best quarter but look at last year we see that Q3 was $128MM, followed by $165MM in Q4 and then $149MM in Q1. Using Q3 as a proxy with $208MM that would imply around $265–270MM in Q4.
Taking even the higher range at $270MM that would mean full 2017 year revenue: $808MM
With revenue growth slowing, user acquisition slowing, and monetization on a per user basis only increasing around 15–20% per quarter that would imply a difficult and challenging 2018.
Most likely full year revenue growth will be around 60% on the high end implying:
2018 full year revenue: $1,292MM
Keep in mind that losses are also growing this entire period so they are treading into Twitter territory of slowing growth and increasing costs.
Taking an 8x revenue multiple on next year’s revenue that would imply a value of: $10.3B today.
However, by Q1 2018 earnings reality will set in. Either Snap will be able to reinvigorate their growth, or with full year 2018 revenue projections it will be quite clear that people are continuing to pay a significant premium for future revenue that is quite possibly 2–4 years ahead of where the company is today.
What's important to understand is that Facebook as a platform is designed for advertising. It's an entertainment platform, people are wasting time so ads fill into that gap nicely and FB has been tweaking everything from how your news feed operates to forcing brands to pay to reach their followers all geared towards increasing revenue.
Twitter is also a good platform for advertising but again look at the frequency of ads that you see, notice that they don't charge to reach followers, and so forth.
Snap is in a worse position because primarily it's a messaging platform which doesn't lend itself well to ads and video ads always under perform because there isn't as much of a driver to interact like click through text or visual ads.
Snap will not get their growth rate next year will decrease, the only question is how much.