I'm an estate agent living and working in the East Yorkshire town of Beverley, which three years ago was named as the most "affordably affluent" town in Britain by the Royal Bank of Scotland's annual Affordable Affluence report. This basically means I work in one of the most up and coming middle-class towns in the country, and as I've worked here for long enough to have seen the town become more and more middle class, it also means that I have noticed a few signs of such middle-class transformation.
The main ones are shops; in fact the most important by a mile is M&S Food, whose arrival anywhere will immediately attract the interest of the 4x4-driving, Boden-wearing buyers; I think there's a good argument that it adds a few percent to prices, especially for the right sort of house. Waitrose also makes a difference, though not as much as M&S Food.
The thing I noticed the most though was that as Beverley attracted more affluent and ambitious 30 and 40 somethings, the cooker hoods became more and more adventurous. A couple of years before the town came top of the survey, I kept visiting homes whose kitchens had not only the steel and curved glass chimney effect hoods, but also cylindrical affairs above island-hobs, hoods done in different colours (mainly red), hoods disguised by fake Victorian mantelpieces around the cooker and various curvy, brushed-steel models. They have become more outlandish as time has passed, and while renovation has definitely slowed as the market has, I'd say the cooker hood is now definitely up there with the coffee machine as one of the main kitchen status symbols - and it definitely adds value to the house, with prospective buyers often remarking on their desirability.
I'd even have to admit it's getting to me; I secretly covet Roblin's R2D2-like N'Khan, and am hoping to convince my wife that it would actually be a solid investment in our property.