Infoworld is an excellent magazine. For example, go and read the latest issue, where F-Secure Anti-Virus Client Security 6.0 beats all the major competitors in a large review.
To quote the magazine: "Support for real-time protection also varies among vendors. McAfee’s, Trend Micro’s, and Tenebril’s versions allow the malware to install, but prevent it from executing, thus leaving it installed but neutered until a removal scan is started. Others, such as Sunbelt CounterSpy, block most malware installs while missing others, and, like Trend Micro, remove existing traces on next scan. F-Secure did the best job of preventing initial installations, blocking all spyware and malware attacks."