Whilst I can see the benefits of a raw diet and would not be against feeding a very carefully planned raw diet to my two cats, people should not always confuse 'natural' with healthy. I know a lot of people on here feed raw, and do it very well following good diets, however some people do not have the knowledge to do this and do not provide an adequately balanced diet.

I have some veterinary knowledge, and during research came across a study which was very interesting: Role of Diet in the Health of the Feline Intestinal Tract and in Inflammatory Bowel Disease
Progress Report (Glasgow et al) . To summarise, two groups were set up (one raw rabbit, one kibble) after one month there were no differences in terms of growth rate, degree of inflammation in the intestinal tract and the numbers of bacteria in the upper small intestine, although a slightly higher number of cats in the raw diet group were shedding pathogenic organisms (Giardia and Cryptosporidia) in their stools (so zoonotic diseases are a risk some may wish to consider). It was noted however that those on raw diet had more solid and less smelly stools! (which many cat owners would rather be cleaning out of their litter trays I'm sure). After 10 months one cat from the raw diet group died suddenly of cardiomyopathy which was attributed to lack of taurine (an essential amino acid cats cannot make themselves and have to obtain from their diet), which could have been due to low levels of taurine in the rabbit (or bacteria in the rabbit caused it's breakdown, or vitamin E levels in the meat were also low). Upon investigation 70% of the cats in the raw diet group had breakdown of heart muscle that is consistent with that seen in taurine deficiency. This investigation is obviously only one of many (and as with any investigation has its flaws, such as cohort sizes), but does hint at some of the positives and negatives associated with a raw diet. Of course, supplements could ensure the cat receives sufficient taurine, and this was added to the raw food group after they discovered the cats were taurine deficient.