I've had the occasion to do a fresh install of dropbox on a couple of windows PCs recently, and both times I've discovered after the fact that the default windows autoplay setting was changed to enable silent uploading of files to Dropbox's photos folder. This setting had previously been set to simply open the volume in file explorer.
This is appalling from a privacy standpoint. No, no pictures of my kids, or (to avert sniggers) compromising pictures of me, or my partner, or any other images I absolutely don't want online were uploaded. They certainly could have been though, if I didn't just happen to realise the setting was changed when I used a usb stick after installing dropbox.
Whoever thought this default was a good idea needs to consider whether it really was worth the risk of compromising users' privacy. It should not be a default setting. It's outrageous it's a silent default setting. If it was an option stated in the dropbox install that I missed, it was nowhere near obvious enough - and still shouldn't be a default.
Rant over.