Random posts from the Cinematography Mailing list describing how to make video look more like film: 

Desaturate, particularly reds and blues. Also lower the luminance a bit in those two colors.
Add grain.

A nice little post trick is to put a very slight blur on the blacks only.

1. Make a second layer of the footage on top of the original.
2. Put a slight blur on the entire bottom layer.
3. With the keyer, key out the deepest black on the top layer, revealing the slightly blurred bottom layer.
4. Feather the key so it's not a harsh delineation.
5. On the bottom layer, adjust the amount of blur to taste. This will give you a rather filmic "velvet" look to the blacks without blurring the whole picture. The whites will still be tack-sharp.

This gives the same effect of placing a light diffusion in the telecine path; since you're dealing with a negative, the highlights on the negative will be blurred, thus the blacks in the positive picture.