Why this is better than a syncing approach is not clear to me.
I was hoping the "new spin" would be something a little more radical.
An example: if I have a 320GB local drive and Dropbox keeps all its files on my local drive, I can't store the full 1TB of files in Dropbox that I'm paying for. However, I probably don't need all of those 1TB of files at the same instant, just various subsets which change over time, meaning that a cloud storage solution which doesn't require constant client-server sync lets me actually utilize the full volume of the service.
https://blogs.dropbox.com/business/2016/04/announcing-projec...
On serious note it would be very nice to have a choice in dropbox about what stays locally and what is cloud only. I don't understand those things that well but I suspect it would be relatively easy for them to add that if it's becoming a selling point for the competition.
They must think they have more potential selling points if they are getting 77M.
Competes more with iCloud than Dropbox. Will probably try and get acquired by Apple/Google.
Those two things aside, Dropbox is very poor. They don't have multi-account support. (There is some abomination where you can combine exactly one personal account with one business account, in a frankenmonster hostile user experience.) Their activity logs don't tell you which machine made changes, only which user. The mobile app doesn't sync, but many users think it does. I don't know how competitors differ in these kind of things, but that is because I use Linux.