In my opinion, there is no best antivirus program. What the magazines tells you is the one that caught the most of THEIR virus samples installed. And their samples may be old. It all depends on what virus you encounter. That said, Norton supposedly catches a lot, so it may catch the one you will encounter. BUT, new viruses are appearing by the MINUTE, and thats why Kapersky is sending out signature updates every hour. And thats why there is a site called VirusTotal which scans your uploaded file with 39 antivirus products to give you a broader view of what all other antivirus companies think. You have to realize that to identify a virus, the firm has first to capture it, then analyse it and come up with an identifying signature. So if they havent caught the one you encounter before, their product will be worthless to you at that time. The thing to do is not fully trust any one antivirus program, but do have one installed. Then suppliment that with several online ActiveX based antivirus scanners, like TrendMicro's Housecall, Panda's Activescan to name just two.
The one you choose to install will depend on whose technology you trust. All antivirus firms realize by now that their signature list is incomplete. And devised some behavior based detection. So besides matching what you just clicked with their signatures, they try to watch what the program does. Some inspect the program for tell tale signs of suspicious code. Its all trade secret of course, and no one knows what exact methods they use or HOW EFFECTIVE their methods are. So here's where you add in marketing and sales hype.
So, choose one to install, and suppliment it with online scanners.
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