I 100% agree. Having the attitude of "I can't get a virus" is pretty dangerous if viruses truly start to hit OS X.
I think a solid example of this is when users state that a malicious program will have to prompt the user for their password to do any "true" damage to the system. Well, if users have a mindset that "I can't get viruses" I'm willing to bet a solid majority will enter their password without thinking twice.
Bleh, Symantec as in Norton? My family used to have that on all of our Windows machine, it slowed them down like mad. When we go Comcast cable, we got free McAfee, it's really sped up boot up times.