Hooking up the Internet to my filesystem is scary. What security measures are in place to ensure a compromise of your infrastructure doesn't compromise mine?
I'm not certain what exact scenario you are referring to. Do you mean if someone is able to install malware on our backend system will that malware get sent to you? Is there something in particular that we are vulnerable to that doesn't also affect Google Drive, Dropbox, iCloud Drive, OneDrive, etc.?
With Google Drive, I choose which files to upload. It doesn't have broad access to everything on my computer.
Dropbox, iCloud, and OneDrive are just backup services, so in theory they could just back up your files as an encrypted blob and have no way to read them. Unfortunately, they don't encrypt them (which is partly why I don't use those services). But at least I have their "promise" that they won't read or analyze my files, which would make me feel better even if its a weak promise.
On the other hand, your service, by nature, is reading an analyzing all of my files using a remote server.