Speaking to various people around the country I've found the pet names vary eg Cockneys use "darling" and North West use "love".
One thing I've found unique is the Stoke people, they use mainly "duck" but occasionally "shug". I didn't quite hear the lady properly the first time she called it me and thought she was calling me a "slug" which I was quite surprised at as I didn't think she knew me that well
