I have a feeling our collective leg is being pulled:

"The behavioural components of happiness are less easily characterised but particular facial expressions such as 'smiling' have been noted"

"Certainly, if television soap operas in any way reflect real life, happiness is a very rare phenomenon indeed in places as far apart as Manchester, the East End of London and Australia. Interestingly, despite all the uncertainty about the epidemiology of happiness, there is some evidence that it is unevenly distributed amongst the social classes: individuals in the higher socio-economic groupings generally report greater positive affect which may reflect the fact that they are more frequently exposed to environmental risk factors for happiness."

...pretty hilarious if you ask me :)