This from a company whose latest product (2012) rated a 5 out of 10 by MaximumPC. In one test, McAfee said the system was clean. Malwarebytes detected more than 40 infections, including a MyDoom variant that sabatoged 25% of MaximumPC's CPU.
Also, while testing it's protection on the web by going to some of the more "suspicious" sites, McAfee tried to stop hostile downloads, but it wasn't completely successful. They kept having file after file show up on their desktop. As they clicked them, McAfee required a reboot to remove the offending file and even after they rebooted numerous times, they STILL had an infected PC.
So, this article from McAfee to me is something to take with a grain of salt.