Ryan over at CyberNet news mentions that virus.gr has posted an updated ranking of anti-virus vendor effectiveness.
The top three positions are held by various forms of Kaspersky:
Active Virus Shield by AOL is a freeware version of Kaspersky. While the AOL label may turn a number of folks off it, at the heart is uses the same program files as Kasperky's self-labeled products.
Two other popular freeware anti-virus products also rated pretty respectively.
I'm a long-time fan of AVG Anti-Virus Free. The version tested was a $ bundle of both the Grisoft anti-virus and anti-malware products...so I'm sure it rendered a bit more coverage than AVG-Free alone.
I practice safe-computing so the efficacy difference in % between AOL's freeware version of Kaspersky and AVG free wouldn't be enough to make me desire to switch, but if I was installing an AV product on a friend or relative's system and wanted a bit more protection coverage, I would really give it strong consideration.
Virus.gr has the full article and anti-virus test list. It's well worth looking at. They also include some interesting test-notes to put it all into context. For more virus testing information, consider going to both the AV-Comparatives and the ISCSA Certified Anti-Virus Product page. Good research information.
Bonus Malware Tools
RogueRemover (freeware) is a MalwareBytes utility to help remove rouge antispyware and antivirus programs that get installed. It doesn't target "malware" per se. Just a particular class of buggery anti-malware products that do more harm than good.