Regarding blocking worms and virus? I use Norton AntiVirus2008. So lets take the example of
W32.Waledac
I see today that Norton/Symantec has been able to detect this and that it usually comes via an e-card.
So lets say I just updated the defs for my NAV2008. So now I get an ecard with this attachment. So like an idiot I open it. But the fact that my defs are updated to block this (assuming it hasn't mutated), tehn i most likely would not get infected?