Kurzweil believes computer intelligence is advancing so rapidly that in a couple of decades, machines will be as intelligent as humans. Soon after that they will surpass humans and start creating even smarter technology. By the middle of this century, the only way for us to keep up will be to merge with the machines so that their superior intelligence can boost our weak little brains and beef up our pitiful, illness-prone bodies. Some of Kurzweil's fellow futurists believe these superhuman computers will want nothing to do with us—that we will become either their pets or, worse yet, their food. Always an optimist, Kurzweil takes a more upbeat view. He swears these superhuman computers will love us, and honor us, since we'll be their ancestors. He also thinks we'll be able to embed our consciousness into silicon, which means we can live on, inside machines, forever and ever, amen.
For one it’s an insult to call our brains weak, considering they run an estimated 20 Peta flops and are smartest machines we know of. The current best supercomputer only runs at about 1 Peta flop and we still don't have the kind of software needed to fully realize it’s potential.
The emergence of artificial intelligence that is indistinguishable from human intelligence does seem plausible. Considering the extreme difficulty of interfacing a living organism with silicon, I doubt that we'll become a cybernetic race anytime soon. Kurzweil's dream of embedding his consciousness into silicon seems highly unlikely to me.
Edit: I think its important to keep an open-mind regarding any future technology. People once laughed at the idea of flying or landing on the Moon.