Colour

To be honest these dolls are fairly creepy and could be easily be interpreted by the audience as being evil more than good, but to give the correct emotion the directer selects brighter tones and shades to open up with, gold and light browns, which relate to safety or holy, and as 9 is created we just take in that these dolls were made for a purpose, to help "life go on" in the "dieing world". This is important as we don't want to be confused at all who the real good guys are in this movie, and it gives our support and sympathy for their loss through their brawls with The Machine.

Comparing colour of the creation and waking of 9

However after the short title coming up onto the screen everything changes, the colour palette only consists of blacks, a range of grays and rusty reds. These colours so nothing but emphasize the dead lifeless world that 9 is born in. These tones set the mood and setting immediately, giving us the post apocalyptic feel this movie is based around.
As the Catbeast comes into the scene however, the first thing we notice is his bright red eye which does two things. It gives the beast life, even though it is fully mechanical, and immediately gives the beast an evil tone. This "red eye" motif runs through all the mechanical villains throughout the movie, with the Catbeast, Winged Beast, Seamstress and of course the The Fabrication Machine/B.R.A.I.N, also running through as a motif for evil in the movie.

First real shot of the Catbeast

Other CG movies seem to generally use very bright and cheery colours, but "9" uses very earthy tones, something you don't usually see, and it gives it some grit and texture, some depth just through the colour palette. Even though the palette is very tight, there is a lot of colour, and it reflects on the extreme care and control used by the art department from the film.