These topics fascinate me! I would have take issue with Rempy's diagnosis of Geogimama's class, just a tad though. I think Rempy is spot-on that she is middle-middle class, but I don't think she is upper-middle, or ever could be. I think anyone who falls into the bracket of upper middle or just plain upper has been born there, and stays there to the death irrespective of what fate has in store for their income. They live by a quite bizarre and exclusive set of codes and ethics that are designed to identify them to one another, and guaranteed to out any imposter within seconds! They are the least socially mobile of the lot. A person born working class can drag themselves into middle classdom through earnings or education or both. Though if they earn a fortune but still behave in a resolutely working class way they will not be regarded by truly middle class people as MM, just as slightly embarrassing Noovs. But even this I find, is very much a relative thing, depending on the angle you come at it from.
I think the majority of people these days fall into the bracket of lower-middle class. They may have had working class roots but aspirations and opportunities (e.g. getting onto the housing ladder via buying their council house) have moved then on a few notches. Middle-middle class people will frequently stem from a MMC background themselves,though many of them are from a LMC or WC background. The reason they are the most difficult to define accurately is that they have so many groups and sub-groups and off-shoots! It's becoming increasingly difficult to accurately define a person's class (and thank God for that) as unless you are a polo-playing land-owning Toff or a member of Karen Matthews' immediate circle of aquaintances it can be quite hard to tell who has come from what these days. I am in agreement with the person who said that the most reliable social indicator is probably the newspaper. Or my personal class barometer of choice, the hairstyle....97% success rate every time! At opposite ends of the spectrum even faces can have the owner's class written all over them!
I think the reason it is so difficult to define someone's class is that ultimately it has little to do with their income. It's a quite deliciously intangiable set of criteria encompassing accent, values, standards, education, job, your parents' jobs, where you choose to live, how you vote, if you vote at all, how you choose to eat, where you choose to go on holiday, what you name your children, what you would and would not wear, how you parent your children, and in particular your attitude to their education, your attitude to money and conspicuous consumption, and a million other subtle and not so subtle indicators. If we wanted to reliably pigeon-hole people these days we'd have to give out multiple choice questionnaires then catalogue each each person on a points system!