At this moment, it looks like no deal. There will be a few more hours of frenetic negotiations, but the best that can be achieved in Copenhagen seems to be a political statement of intent. Even if there is a last minute binding agreement, it will be a much watered-down version of what was needed.
Even if there is no agreed text at the end of the day, it should not be the end of the process. Hyped-up language is always a part of these summits, but this time, there were some who really made it sound as if failure in Copenhagen will lead to the destruction of the planet and the end of the human species. What is needed is level-headedness and a political will to continue negotiations. I would only start to worry in earnest, if these two things were to disappear into thin air, once the summit ends without result.