If you are looking to see what people use and nothing else then goodluck - if you are looking for a debate, discussion, or reaosn why people use them, then make a search called antivirus or anti virus in the website, this isue has been brought up many many times and I myself just dont have the effort to desire to post reasons for what seem sliek a 100th time.
If your just curious, I am using norton 2007 anti virus NOT SYTEM WORKS AND NOT INTERNET SECURITY OR 360 because all those products are garbage.