Another thing that's changed are kitchens - seating and dining to be precise. When we bought our first house in the USA we gutted it (as you often do here) and turned three teeny rooms into one huge kitchen. The kitchen not only housed an L-shaped cabinet and appliance corner with a six foot island in front, but a large kitchen table, six dining chairs, a sofa, an easy chair and a TV. Yes, that big - although not particularly big by American standards. American houses have long had live-in kitchens, often leading straight into the living and dining rooms with no walls or doors in sight. This floor plan shows a typical American (new) home. Note the distinct lack of hallway - you come in the front door (through the smaller covered porch) and land smack in the middle of the family room,
Here's an article that discusses the evolution of the British kitchen, from table to Breakfast Bar (remember them?) to islands. I'm rather fascinated I have to say.