The Register: The average PC: spyware hotel

A headline grabbing release from Earthlink claimed that a large study it conducted on about a million computers revealed the average PC contains 28 pieces of spyware. But looking at the study itself, the vast majority of these "spyware" instances are merely site cookies (about 24 million of them counted). More seriously, it did find about 360,000 trojan horses and system monitors, applications used for theft and fraud.

The study found more than 5 million instances of what it alternately calls spyware or adware, without breaking out how many of one versus the other. Most define adware as programs voluntarily downloaded that happen to be paid via advertising, whereas spyware sneaks onto computers surreptitiously and conducts functions without having first secured explicit permission.

Real users will probably not be very concerned about the 20-some-odd cookies on their computers. They will definitely be startled to find that one in three has a keylogging application or equally nasty trojan on their machine. They will also be concerned about the average 5-per-machine instances of adware and spyware to the degree they didn't already know and approve of any of those instances.