Originally Posted by KenJohn
Butler service = room service from a dedicated member of staff so you know the face or faces (one during the day and one in the evening) so the person you are dealing with.
It is really standard room service by all hotel service staff hand off to the butler (meals, laundry, amenities, etc) who will then deal with you direct.
The only time other staff enter the room is during cleaning.
At St. Regis it's not even this...there are a pool of "butlers", with no particular connection between any one room and a single person. I agree that it's just a repackaging of standard hotel services...less pretentious hotels tend to call it "guest services" or something similar, but there's really no significant difference.