Hi All, I'm new convert and LOVE my MacBook Air. There is something, however, that keeps me up at night. VIRUSES/SPYWARE/WORMS, etc... I've read some posts here and what I'm getting is that an Anti-Virus program is not necessary on my Mac. I do have Norton AntiVirus 10.2. Is that enough? What about firewalls, spyware, etc... After years on a PC, I'm addicted to these things... Please help me put my mind at ease... Do I need them? Should I upgrade to Norton Internet Security?