As far as the sensor is concerned, the important factor (as noted above by others) in color reproduction is not the density of the color filters (or their spatial arrangement in a mosaic pattern such as Bayer), but rather the shapes of the transmission curves and how they relate to each other. Ideally from a color perspective, you'd want the transmission curves to be the same as the human cone responses (in the eye) or a linear transformation thereof. But there is a tradeoff in terms of color vs noise, and of course there are other practical constraints due to materials, manufacturing, costs, etc., so in practice this technical condition is not satisfied. as I mentioned earlier, this is rather a separate issue from the choice of CCD vs CMOS.
But as far as photography is concerned, my experience has been that color response differences from system to system have less to do with the sensor, and more to do with the software rendering applied in post-processing (even if the user never touches any sliders or controls). Example: Canon has various Picture Styles (such as Portrait and Landscape) available in their software for their cameras, some of which have CMOS sensors, some of which have CCD sensors. The difference in visual appearance between these software-based styles is far greater than the actual differences in the color filters!
Ray, I generally measure camera optical systems with a monochromator to estimate the transmission curves over the visible and near-IR range. However, I don't have manufacturer data sheets for most of the systems I measure (and even for those for which I do, the maker's data is usually for the sensor alone, whereas I prefer to measure sensor + lens combinations, so comparisons are hard). And you never know -- maybe I was a mad Irishman in a previous life!!