content: I'm pretty sure all your examples are examples of auto execution of software/files.  IIRC the Sony Rootkit installed silently because Windows used to auto-run CDs, also supposedly UAC would have blocked it as well, but that's a bit off track anyways. I'm pretty sure now Windows asks you if you want to run a CD/DVD when you spin one up. USB devices are different than CDs because of the way they interact with the system, as they have firmware that interacts with the system as soon as you plug them in, so it's executing code right away with USB.