I was surprised to see this hoary question exhumed by Gwynne Dyer, in a recent article that argues for the technological deceleration thesis. There was some discussion of Dyer's piece going on over here, but it didn't seem to get far.
I expressed some thoughts of my own back in 1998, in an article called "Singularity Shadow", originally published in Quadrant magazine and available on my website. At the time, I was prompted by some (then recent) claims by Robert Zubrin. While I don't necesarily endorse every observation that I made when I wrote the article ten years ago, it still seems to me that I got basically got it right: if we are looking for physically big things in the landscape, there has not been much qualitative change in developed countries since (say) the 1960s. I.e., we have much the same sorts of big things (buildings, ships, planes, lit-up cities, etc.). But if we are looking at the way technology has become smooth, ubiquitous, comfortable, conformable to our wills, then the qualitative change over the past few decades is impressive and continuing, with computers revolutionising the ways we live our lives - just as the motor car and the contraceptive pill did.
I'm not a decelerationist on this issue - but nor am I a radical accelerationist. Even Moore's law, which involves continuing doublings of computer power per dollar, does not entail that there will be extraordinary changes in our lived experience. An immensely greater increase in computer power sometimes produces little change of human significance, partly because we so often underestimate what is involved even in apparently simple goals such as robotic locomotion. Nonetheless, it is naive to think that modern computer technology, biotech, and such things as new materials, have not altered the way we live and think. We don't need to see gigantic IBM mainframes wandering around the landscape, like Hollywood dinosaurs, to get the point that change happens. Sometimes less really is more.