I really enjoy the new user experience on mobile these days. Really intuitive and works well with native Android features. Particularly think adding new files (multiple at once) has gotten a lot easier. Haven't had a chance use the new sign-up form but it looks great.
I gave up on Dropbox on ipad ever since using Bittorrent Sync. Dropbox started forcing me to keep their app open (to sync). Not going to happen. Bittorrent sync works like a charm to get the photos/videos off of ipad. I don't see a need for Dropbox anymore.
I gave up on Dropbox when they hired Condaleeza Rice as a board member and consultant while they build out their solution for shunting everyone's data to the NSA.