Many people are forgetting that viruses can simply erase all partitions rather than corrupt data. That to me poses a much bigger threat than data corruption. Read-only drivers please!
Read-only drivers won't protect you from having its partition deleted, it can do that without even having any kind of drivers in the first place.
Viruses are very slowly dying out to torjans. The authors are now trying to make it into a business to make money by blackmailing or by controlling the computers as a botnet.