Making NIS a complete package

Yesterday my Vista SP2 PC became infected with malware and was surprised and a bit annoyed that my updated version of NIS 2009 did not catch it.  After a full scan of my system, NIS detected zero threats.  I downloaded and installed Malwarebytes which detected 13 locations (file, registry, etc) where threats existed.   I used Malwarebytes to remove those threats and my PC is back in working order.

 

My question is why does a free (mostly) software provide protection that NIS doesn't?  While I understand that all Anti-X products are going to vary in their effectiveness the fact that I pay for 'advanced' protection from Symantec's Norton NIS product line, which failed to detect ANY of the 13 threat locations a freeware program did, astounds me.   In my mind, I envision a large team of developers working for Symantec developing NIS contrasted with a much smaller less endowed team developing Malwarebytes yet this freeware has done something NIS could not.   

 

Furthermore I understand that NIS does a whole heck of a lot more than MBAM does but my point if the reciprocal of that.  Why can't NIS, as full-featured a product that it is, which advertises root kit and malware removal not find any of these threats that MBAM does?

 

My NIS subscription runs out in 16 days and so my query is hoping to uncover reasons for or against upgrading to NIS 2010.   I am going to do some reading but I suspect there are some other retail Anti-X products out there that may have a more improved malware detection.

 

I really like the improved scanning and streamlined NIS interface introduced in 2009 but if it isn’t doing a good job of detecting threats I have to consider those improvements less important.  Heck, maybe NIS 2010 is simply that much better and it would have detected these threats.

 

Please see the attached image (screenshot) to view the two products detection side-by-side and you can see the marked difference and detailed threats which MBAM unearthed.

All friendly and constructive comments welcome.

 

http://picasaweb.google.com/lh/photo/u-iXrMUeUgBEI4PPKvw7wDbj_ZwY4RY2XS7QtvEwRW4?feat=directlink