http://cgi.gamefaqs.com/poll/index.asp?poll=1186 (Gamecube)
http://cgi.gamefaqs.com/poll/index.asp?poll=1187 (PS2)
http://cgi.gamefaqs.com/poll/index.asp?poll=1188 (XBox)

Seems a very large portion of GameFAQs regular have Gamecube and/or PS2 but very few would buy XBox. Either it means there are not many XBox fan at GameFAQs or M$ lied about the number of XBox units sold.