I have been using Dropbox occasionally over the last few years to sync files (installers, etc.) between multiple computers. I never felt comfortable about using it for things I am working on (and private files), especially since they did not provide any form for encryption of the files. After the Dropbox security problem a couple of weeks ago, and the updated terms allowing them to look at your files, if needed, I am even more suspicious about using Dropbox for anything.