I turned off USB debugging, since it's entirely pointless for me (I run Linux boxes, so ADB is not an option anyway) and I was annoyed by the notification. Now, whenever I plug the usb in to a computer I get a full-screen notification asking me if I want to mount SD card to the computer. Where the heck did this come from? I've never seen it before. And more to the point, how do I turn it off? I absolutely despise interfaces that try to "help" me. 99% of the time, it's not helping.