The monocoque (‘tub’) is the most important core of the car, other parts are put onto it, generally everything.
November 10.: Exclusive picture about the MP4-25, (intentionally partly blurred)
November 23. (or a couple of days earlier): Campos Meta 1, Bruno Senna seat fitting
December 15.: Virgin Racing publishing a video showing the car and Timo Glock seat fitting
December 22.: First picture of the US F1 chassis, December 24.: first video, screencap
December 23.: Sauber pictures, Kobayashi seat fitting, picture 2, more pictures here.
More to come, most probably in the form of car debuts.