writes "According to statistics generated by Microsoft's new free malware scanning and scrubbing tool, Safety Scanner, one in every twenty Windows PCs are infected with malware. Microsoft's Safety Scanner was downloaded 420,000 times in just one week of availability and it cleaned up malware or signs of exploitation from more than 20,000 Windows PCs, according to statistics generated by Microsoft's Malware Protection Center. This resulted in an infection rate of nearly 5%."
That seems an awfully low number, based on how quickly Windows machines are scanned for plunder after going online; though it's a few years old, here's a report that suggests (as of 2007, at least) a grace period of less than 10 seconds
. That was just one instance, and an intentionally vulnerable machine, but have improvements in security software software, and in Windows itself, made things so much better since then?