Effectiveness of Spam control

As a new and generally satisfied convert to NIS2010, I must admit to some disappointment with the spam-blocking feature, which reviewers had called a big improvement over last year’s model.  These days I’m not getting much spam in absolute terms – just one or two a day – but Norton has missed the last four in a row and probably close to half of all spam since I installed the program a few weeks back.  (Only one false positive, at least.)  What are other people finding?