If one thinks of postcodes as merely a bit of stuff you write on a letter to help the postman, it may not seem like such a big deal. Though once postcodes are seen in a broader context, as coordinates optimised for specifying how to get to a location, they really come into their own. A 4-digit Australian postcode gives a few square kilometers of urban area, or several times that in the outback. A 6-7 character British postcode, however, can home in on a street or a segment of a street, down to a few dozen houses. Type in a postcode like "NW6 7JR" into Google Maps and you'll get a map showing you where your destination is; enter it into something like the Transport for London Journey Planner, and it has enough information to determine an optimal route for getting to the location in question, getting you close enough to find your destination without any further help. Because the postcode is a code in a very specific format, there is no need for guesswork, address parsing, or the computer asking you to select which location you meant from a list of alternatives.
I modestly propose that Australia would benefit from street level postcodes. The increased efficiency in mail delivery would save the Post Office money, and the streamlining of computer-based navigation technologies would boost the increasingly high-tech, high-speed economy, not to mention provide a valuable public utility. One could possibly even make an environmental argument for finer-grained postcodes, that in optimising navigation, they would reduce the amount of fuel used and pollution emitted. The street-level information could be added on as a suffix to existing postcodes, much in the way ZIP+4 was added to US ZIP codes in 1983, and could consist of an alphanumeric suffix. For example, a segment of a street in Fitzroy could be designated by something that looks like 3065-AB3. (They could also be purely numeric, though alphanumeric suffixes would allow for more information in fewer characters, and keeping the total length to 7 characters or less (as per The Magical Number Seven +/- 2, this being the capacity of human immediate memory) Punch that into a website or mobile phone application and you can get detailed instructions on how to get to your desired location.
Of course, proposing such a scheme is one thing, and getting bureaucrats, politicians and various vested interests to run with it is another, so one probably shouldn't hold one's breath.
And if it never happens, we could always move to a purely latitude/longitude-based coding system like the Natural Area Coding System. The problem with that is that, being purely physical, it does not take into account local geographical features, such as whether two points are adjacent houses on a street or houses in two streets only reachable by a long detour.
Please keep comments on topic and to the point. Inappropriate comments may be deleted.
Note that markup is stripped from comments; URLs will be automatically converted into links.