Can't believe this thread has gone on so long without mention of Ray Kurzweil!
If you haven't yet, I'd suggest you all check out the documentary about him called
Transcendent Man. Basically everything being discussed here is touched upon by top scientists in their respective fields, and while no one is in agreement on the time frame of these technologies' existence, no one can argue the accuracy with which Kurzweil has made predictions about the advancement of technology in the past based on his models. He is possibly the world's most successful futurist, and while his latest predictions are perhaps tainted by his own mortality and a childlike (albeit depressing) desire to bring his father back to life via AI, I feel the future he describes may be right around the corner. He describes an event he calls the Singularity--when humans will merge with the intelligent technologies we've developed and artificially kickstart the next phase of human "evolution." If we don't see it, our children just might.
Either way, it's a very thought-provoking documentary with input from people who address these issues for a living, including
Hugo de Garis--formerly employed by a Chinese university to build an artificial human brain, and
Kevin Warwick, who is essentially a work-in-progress cyborg already.