I've read it. I didn't really like his thesis. He seems to think that there's a drive towards intelligence, naturally. I don't really buy it. I also have serious doubts about the viability of his escalating returns: at least at the scale he presents it.
Right now we're geometrically increasing the number of scientists, and this can explain the current tech-curve. Eventually we're going to be slowing the rate at which new educated innovators are added to the pool, as 6 billion people modernise. As well, the amount of time it requires to become a contributor to scientific knowledge continues to increase.
I like his snapshots of technology. Kurzweil has also done two TEDtalks.