In a recent interview† with Dave Kennedy, he in passing pegged the average effectiveness of anti-virus products as detecting approximately 3% to 5% of current active threats.
While AV comparisons will typically publish detection rates, those are always based on historical virus samples which are only mildly relevant in today's security landscape. Current virus and malware activity is inherently difficult to properly gauge.
Do we have any scientific measure of the real-world effectiveness of off-the-shelf anti-virus products in detecting and stopping today's active threats?
Put differently, what is the actual real value of running an anti-virus product when facing today's common security threats?