The "Crick-Koch Conjecture" is that the difference between conscious and unconscious processing is that in the conscious processing the relevant neurons fire in synch, producing (gamma) oscillations. Basically, the conjecture is that the temporal synchrony of the relevant action potentials is what creates a conscious sensation.
This is not the first time people were trying to link neural oscillations and synchrony with consciousness. However, whether this conjecture is right or wrong, after this paper it again became acceptable to address and study the issues of consciousness in the mainstream neuroscience. The reason is probably the combination of Crick's reputation (he achieved seminal breakthroughs quite a few times in his life) and of the fact that this paper is very well and clearly written. If someone wants to read one paper in theoretical neuroscience, this is probably the paper to read.
Crick and Koch remark that one does not need to formally define consciousness in order to study it: "Everyone has a rough idea of what is meant by consciousness. We feel that it is better to avoid a precise definition of consciousness because of the dangers of premature definition. Until we understand the problem much better, any attempt at a formal definition is likely to be either misleading or overly restrictive, or both."
I hope the next year will be better than the outgoing one...
Good luck in the New Year!