My hunch is that consciousness will come to be described in terms of information processing systems, rather than the biological substrate on which they run. Systems with certain properties - possibly including a sufficiently complex model of the environment, model of the self, and a continuously updating internal narrative - may be said to possess a level of consciousness. I'm not a biologist and I appreciate that the above is somewhat vague, but I wouldn't say that sperm or egg cells have the above.
