the topic reads "Why computers will never be conscious" not "Why computers are not conscious"
to me this is the point. if our design of computers froze today consciousness as we define it wouldn't be possible in a computer but in reality computer design isnt static.
Someone else pointed out that,
now granted we are a long way away from being able to make anything nearly this complex now but im not aware of any law that precludes this in the future. since biology can already do it we know its at least physically possible."for a machine to be a conscious in a human fashion all you need is to emulate a body and an hook it up with reality."
saying computers will NEVER be conscious, period! is a pretty big assumption considering how little we understand about consciousness and the fact that computing is still in its infancy (its barely reached the zygote stage).