You just need to look at the state of thing now and how everything has being going for the last year, clearly Dropbox has all the momentum and usability. How many conferences have you seen Box's ceo at, that guy is at every conference and Box is supposed to be a startup. Box was the first cloud service i used, then moved onto Dropbox because the usability was just amazing. I also think Dropbox may have better engineering talent because the syncing works so much better than ubuntu one,drive and box.