How will science shape the human?

I watched with interest How will science shape what it means to be human on ABC2 last night, with various panelists from the fields of psychology, ethics, technology, physics, medicine and business.  Paul Davies was the only person to use the term 'post-human' but grappled with the notion and this might be, because in my mind at least, it is only by freezing a point in time - like now, that we can label the moment of change as something definitive, whereas in fact the humanimal has and always will be a potential to be something other than, or different to its present state of being.  Peter Singer thought it would be more fruitful to ask questions other than what it is to be human and that we might consider instead how future science might develop strategies to make us more ethical & less aggressive. One can only presume that he meant using genetic tampering to rid us of undesirable genetic traits and diseases, but he did not discuss whether this might be an ethical endeavor. The panelists did agree that future developments to physically and mentally enhance the human, would most likely be accessed by those who could afford it, creating a divide. The suggestion that access to enhancing medicines or technology would be equitable was just outrageous, since millions of people world wide live in poverty and that $1,000 fee to have your own personal genome sequenced for designer drugs, stem cells or gene modification to cure your current or future disease, would be out of reach for many people in the western world. I couldn't help but think of the film GATTACA whilst watching these well paid academics speak of a future in which science and technology will change our current notion of what it means to be human. On the point of desirable or undesirable human qualities, Liesl Capper-Beilby who has been developing 'conversational agents' (a computer system designed to converse with a human) for older or less mobile individuals, noted that if the conversational agent, as companion, was too amiable (that is, not aggressive enough) then individuals were less like to see the 'machine' as human and therefore not likely to interact with it. It seems that rightly or wrongly what made us human may have been our aggressive streak, our ability to fight for what we wanted and instigate change. She spoke of a future scenario in which those who were housebound or confined to a wheelchair could deploy virtual avatars to complete some of their social and business duties. However, I'm wondering if we are already, as Paul Virilio has said,the equivalent of the equipped disabled, since we rely so heavily on the internet and our communications technologies. Almost gone are the days when we would write a letter and go down to the post office to post it, or look forward eagerly to receiving correspondence in our letter box. Luckily, I don't fall into that category for I still have friends who send little things in the mail. Nostalgia is definitely human and I suppose that as the years go on there will be more nostalgia for the past?