Justifying billions is of course a stretch, but having a really, really smooth UI definitely does make a difference. Its easy to underestimate these things in f

Justifying billions is of course a stretch, but having a really, really smooth UI definitely does make a difference. Its easy to underestimate these things in favor of technological advantages, which dropbox doesn't really have compared to every other personal file hosting site. But normal people really don't know/care about that, for them all that matters is an easy UI that just works. And dropbox does just that, IMO better than any others