Here is Paul Krugman, noting that innovations for the kitchen have slowed down. He cites this earlier, mid-90s piece of his on kitchens, which I would have cited had I known about it. His conclusion:
By any reasonable standard, the change in how America lived between 1918 and 1957 was immensely greater than the change between 1957 and the present.
As Krugman did in the mid-1990s, I now cook in a 1950s kitchen and it suits me fine.
My anecdote refutes his! Look at your office. From 1918 to 1957, it probably had slide rules, typewriter, desk, phone. But in 2011 we have computers, which are filled with magical programs that do things unimaginable in 1957. After all, in 1954 the head of IBM said "I think there is a world market for maybe five computers."