AV-Comparitives.org, an independent anti-virus testing site, has released its November 2006 results of its "Retrospective/ProActive Test" series that tests the heuristic and generic scanning capabilities of anti-virus solutions.
(Apologies for the late post, as this test was posted back in November, however it should still prove invaluable. Besides, I just know everyone has their own favourites and would like to see the results regardless.)
http://www.av-comparatives.org/ - click on Comparatives on the left navbar and select Online Results for the Retrospective/ProActive Test of November 2006 to see a complete table of the results, or Report for a detailed written summary.