We certainly face plenty of uncertainties when we move from reading the texts to applying CT either in clinical practice or in real-life research. It is much simpler to discuss the concepts than it is to test the theories or to make lasting changes in people's lives.

One area that is still full of uncertainty is the interface between biology and cognition. Another area of uncertainty is the exact relationship between affect and cognition (does cognition preceed emotion, does emotion preceed cognition, are they two partially independent sub-systems, ...). There's quite a bit of uncertainty about the mechanisms through which CT works (therapeutic realtionship vs specific techniques vs ...). Currently, I'm giving a fair amount of thought to another area of uncertainty, CT's approach to dealing with topics such as transference, the unconscious, and childhood trauma that traditionally have been the province of psychoanalysis (see http://www.cape.org/2005/pretzer.html).

There are also plenty of clinical problems where we're debating which treatment protocols are most promising and how to deliver them most effectively. Even with topics as basic as CT of depression, some are arguing that "behavioral activation" is as effective as the full CT protocol and that there is no need to do Beckian CT.

There is no danger of running out of topics to research and debate in the forseeable future.

While there is plenty of uncertainty and much is left to be figured out, I'm not sure that any of this is crucial for effective treatment. I'd argue that we have good evidence that CT works well for quite a few problems. Our uncertainty lies largely in understanding the exact mechanisms through which it works, figuring out how it can be improved, figuring out how to apply it effectively with a broader range of people and problems, and figuring out how to make it available to more of the people who need effective treatment for serious problems.

Yes, certainly the uncertainties we face are a very worthwhile topic for discussion. Which uncertainties shall we talk about?