[jacquesm]

They've talked about that at some length, it is a relic from the early days and even if it costs them money (60 million bucks annually iirc) they feel they should keep it not to upset the users that have gotten used to it being there and occasionally using it.

edit: so much for my memory, it costs them almost twice that, 110 million per year, source:

http://hubpages.com/hub/Im-feeling-lucky-button-costs-Google...