Postcode bingo

We recently moved and apparently we've gone upmarket.  In updating my new address where I volunteer twice a week, I was greeted with the response of "you've gone posh, then."  Since we'd moved less than 1 mile away, I questioned this observation.  It appears that our new postcode, W11, is vastly superior to our old postcode of W10.  Although a stone's throw separates them, the latter is the Outer Limits of North Kensington, while the former is the fabled Notting Hill.  A lively conversation ensued about the relative superiority of postcodes.  Five years ago we used to live in SW3 - that drew an appreciative whistle - which is apparently only outdone perhaps by SW7.  Another co-worker was pleased to note he resided in W1. Etc, etc.  The really curious thing about postcodes isn't the secret embedded in the first three letters and digits (which denote only a neighborhood), it's the last three consisting of a number and two letters that pinpoint your location with the accuracy of a heat-seeking Sidewinder missile crashing through your living room window. Very clever and very MI5!