Now that Dropbox is finally poised to go public there will be two storylines to watch.

The first will be about this era of runaway valuations. Taken together, the decacorns are worth more than $200 billion. These bets are only accelerating. In a single quarter last year, private market investors pumped a record $10 billion into “startups”... and 80% of that went to just four companies

Snap was the first decacorn to go public. To its credit, it is still worth tens of billions of dollars-- it is trading just above its IPO price of some $21 billion in market cap. But it’s vulnerable. Instagram stories has proven a formidable adversary and its youth audience which it argued justified its price is in revolt over a redesign. Snap said it its S1 it would need to continually innovate to keep it’s fad-oriented audience engaged. It hasn’t. Spectacles were a dud. Those same users are the ones who hate the redesign. If a Tweet from Kylie can wipe away $1.3 billion in market cap, perhaps you shouldn’t have made a $20 billion bet on divining fads.

How will Dropbox fare against its four-year-old valuation of $10 billion...?