My mother, who was in the diplomatic scene in Brussels in the late '60s, where hand-kissing was quite usual amongst the continental diplomats, became something of a connaisseur of various styles. She said the French tended to go for the sort of 'air kiss' Gerta describes where the lips didn't meet the hand, Germans and Austrians did a faint brush of the lips, but the Belgians went for a hearty smack of the lips!