That poll does not tell us which firewall is the best. It only gives us an idea of which is more popular amongst NTFS members.
So far, I've been through Norton IS 2002/3, Zone Alarm and McAfee Firewall.
At first, Zone Alarm worked quite well at blocking stuff that was not wanted, however, there were many many occasions where it blocked stuff that was wanted. Next the program itself screwed up (not allowing access to settings) and there was no was to get it back up running properly (even after removing and re-installing).
Norton IS can automatically configure 'some' connections, mainly low risk connections, while prompting a response from the user for permission to connect a particular program to have access to the internet. This is quite good, until it starts popping up in your face every 2 seconds if you don't want to give a permanent setting for that program that is trying to connect to the net.
The other thing about Norton IS is that it doesn't really block pop up windows very well. There is no setting that lets you configure the blocking of pop ups.
McAfee I think has worked very well for me, but I havent used it for very long.
It blocks pop ups perfectly, but like Zone Alarm, it does block some of the stuff that you'd expect to see when you click on a link.
McAfee give you a good control on the firewall, although I haven't actually found the bit where you can enter websites to block.