I think it is inevitable that we will (assuming we don't wipe ourselves out before then) merge with our machines (particularly in the form of nanotechnology). You just have to look at how integrated people are with their external technology to see that it is not a too distant step. Initially it will be to help people with disabilities but eventually it will be for pure enhancement. I don't agree that it will lead to the destruction of human identity - this is not a set thing and never has been. Humanity has always been changing and evolving. This is the next stage of evolution.