From time to time (last time somewhere in December or January I think) I test the effectiveness of NIS by going to Google Trends, look for a popular search (e. g. google search results for 'jesse james cheating' are at this moment almost exclusively populated with malware links, mostly fake antivirus), I click an see what happens (of course, I never infect my machine because I know what I am doing and how I'm doing it - don't even try it if you don't know how to kill a process).
I tried earlier this day with Firefox and IE8, I tried these last few minutes with Chrome and I haven't been able to see a singel Fake AV scan page. If all this is not just a good day, but the result of some hard work behind the scenes, I congratulate Symantec for doing it right, and please do continue. This looks extremely good.
Also, SafeWeb seems to have more of the malware page actually red flagged. Kudos.