AV-Comparatives: Comparative detection capability tests of various popular antivirus products.
AV-Test.org: Tests of anti-virus software on Windows 98, ME, NT, 2000, XP, Linux, FreeBSD, Netware, Exchange, and Notes.
ConsumerSearch: Links and reviews of anti-virus software review sites.
Free Antivirus Info: Reviews of popular free anti-virus software.
PCWorld.com - Install-and-Forget Antivirus Programs: November 2002 review compares latest offerings from Mcafee, Norton, and Panda.
SC Magazine: Products section of site offers over 50 reviews of antivirus products. Other security product reviews available as well.
Software-Antivirus.com: Offer reviews of several antivirus products.
Virus Bulletin: Testing and awards for virus scanners able to detect all viruses that are currently "in the wild"
Virus Protection Software Reviews: Reviews of malware removal and firewall software products.
Virus Test Center - University of Hamburg Computer Science Department: Academic virus research program publishing regular tests of antivirus software.
Virus.gr: Comparative reviews of anti-virus programs, links to virus removal software, and information on specific virus outbreaks.