Hello, NIS 2005 was given with my laptop when I bought it last christmas (yes its old for a computer sold in 2006).
Don't think it was a gift, just a crap on my system so I downloaded the remover and Bye Bye NIS !
Now I use BitDefender Internet Security 10, it's much better than Norton, I added Spybot. My computer is perfectly clean and if I get infected, I know how to disinfect it :D
I think you should add NIS 2004 to 2007 to the PUPS because it's really hard to remove without the symantec remover, like a spyware, and it decreases the computer security by asking the user to remove almost any another security software for the last version (can't use another firewall, antispy or antispam with 2007 I think).
In conclusion NIS is a sh*t !!