What's interesting is that if you study the anatomy of the human body, you'll find more similarities in it's structure to that of a herbavor than a carnivor. The teeth, for example, are flat like thoose of a cow or a deer. The length of the gastrointestinal tract is extremely long; making for a thourough digestion process.
Carnivors, like pigs for instance, have very short GT tracts and ingested food becomes part of their flesh in just a few hours. Cows and other herbavors go through extensive digestive processes to get all the nutrience possible out of their food.
Herbavores require longer digestive processes not for efficiency's sake, but because it's darned hard to digest grass and leaves because of their high fiber content. You
have to digest it thoroughly to get
any nutrition out of it.
Humans are definitely omnivores. Our molar teeth are designed to be crushers, like those of a cow or deer, but our canines are designed to be tearers, like (surprise) a dog. Meat contains fats and proteins which are highly useful in situations where the food supply is unstable, or in climates that are cold. The digestion of protein produces heat, and fats are an excellent store of energy.
Personally, I do eat meat, though it's a pretty small part of my diet. Mainly we eat fish, chicken, ground beef, and venison. The main reason we don't eat much meat is that it's expensive, its preparation is more complicated (and time consuming), and our freezer (until recently) was too small to store much meat anyway.
My favorite meats are seafood (crab, lobster, fish, squid, octopus), lamb, venison, and goat. I like beef okay, we rarely eat pork (except for bacon), and chicken is sort of generic (but good).
My wife and I are avid gardeners, so summer is usually a nearly all vegetable season for us. Fall brings us venison, and winter typically has us eating a larger percentage of meat in our diet.
I've never really understood the so-called "moral" objection to eating meat. From a purely naturalistic view, humans eating meat is no different that a lion eating a kudu. Granted, one may object to the ways in which we produce meat, but surely that's a different objection entirely than the actual human consumption of meat.