And I've got to say -- as a colleague -- he kicked butt. Hardly any "ums" and "uhs" even when unexpected questions forced him to try to explain complicated concepts not covered in his prepared talk. Didn't have to rush, never got boring or bogged down, covered all the material, transitioned smoothly, kept the audience engaged, and clearly knew more than anybody in the room about the project, and knew he knew it. Made a couple of jokes, and got into a couple of interesting side discussions. In short: professional.
But what does this "candidacy" mean? Well, Wikipedia says that at some universities it's an actual degree:
All But Dissertation or All But Degree, abbreviated ABD, or Candidatus Philosophiae or Candidate in Philosophy, abbreviated C.Phil. is a formal academic degree awarded to a student, or an informal status that says a Doctor of Philosophy (PhD) student has completed all graduate study leading up to the final dissertation. This typically includes graduate coursework, preliminary/cumulative/qualifying examinations, and defense of the dissertation prospectus, advanced to candidacy.
Sometimes "C.Phil." or "Ph.D. (ABD)" is used as a title. In the U.S., ABD is an unofficial status, and C.Phil. is an official degree at very few universities.
In some schools a student can write an additional thesis at this point and receive a Master of Philosophy (MPhil) degree; in others, the MA, MS or MPhil (sometimes Candidate in Philosophy, CPhil) is conferred on an ABD student who has been advanced to candidacy for the Ph.D. Additionally, some American universities award the Master of Philosophy to students who have completed the coursework necessary for a Ph.D. but who have not completed the dissertation.
What it means at our university is 1: He can't take classes anymore for credit. He's done being a student, officially. His job now is research. And 2: his tuition (which is paid for mostly out of our advisor's grant money) is now therefor much cheaper. This makes our advisor happy. And of course 3: the last formal requirement left for him for graduation is actually defending his thesis.
My turn will come after I've completed all my required classes, which I'm not planning to do until next winter (which is when the classes I want to take are next offered.) I hope I do as well.