Please read this from BigCats.com and seriously reconsider:
I am surprised by the percentage of survey respondents who don't know about servals. BigCats.com has avoided posting overviews of the cat species because this information is available ad nauseam online. However given the results of the survey, I'll go ahead and talk about the serval basics.
Servals are mid-sized wild cats from parts of Africa, primarily Sub-Saharan Africa. The average size is 11 kg (24 pounds), with a weight range of roughly 9-18 kg (20-40 pounds). This is about 2-3 times the size of a domestic cat, but servals can appear even larger due to their proportions.
Servals are delicate cylindrical looking cats, with petite heads, long necks, and long slim legs. When looking at a serval head-on, their ears dominate, raising high up in proportion to the head. The coat color is a rich fawn on top spreading down to areas of creamy white. Solid black spots of various sizes adorn most of the fur and merge to form bars on some areas of the body. In some parts of Africa, servals can be melanistic (very dark, appearing black, but the spots are still there).
Servals can live up to 20 years or so, which is similar to a domestic cat, although most don't live nearly that long due to the dangers of living in the wild.
Servals eat primarily small mammals such as rodents (preferably larger rodents), but they aren't picky and will take birds, reptiles, fish, and even insects. Presumably due to their delicate bodies, they rarely take larger prey. A documentary from years ago (sorry I don't remember the name) referred to servals as "pouncing radar", which is a nod to their hunting style. Servals disguise themselves in tall grass and use those huge ears to pick out their prey by sound. When the moment is right, they leap in a high arch to pounce down upon and incapacitate the target. A similar technique works quite well for flying prey.
Servals favor but are not restricted to water-rich environments with tall grass. Since people also like to live near water, this arrangement has the potential to create conflict, especially for farmers with poultry, because poultry is the right size of prey for a serval. However, since servals usually prefer rodents, coexistence can actually benefit both servals and people - people want to be rid of rodents, and servals want to eat them.
As an entire species the serval has not yet been categorized as endangered, and in most areas they are not protected. However their global population is falling and they will ultimately need protection. The key to long-term survival is the conservation of wetlands (their favored habitat), as well as the conservation of grasslands which have been damaged by livestock and agriculture. On a more repugnant note, some people hunt servals for their pelts, which can be sold to ignorant tourists, sometimes labeled as cheetah or leopard fur. I guess more people know about cheetahs and leopards, and therefore prefer their fur over that of a serval.
I don't know how many people keep servals as pets, but in the United States at least, serval breeders are fairly easy to find. The resulting kittens are going somewhere, presumably in to homes since servals are not a big attraction at zoos. (Perhaps that is why people don't know what they are.) Servals as pets are certainly not rare. You can verify this with a quick search online, which reveals photo galleries of servals in the home as well as discussions about serval care and legal requirements.
I have to admit that I can see the appeal, that having a serval might give a person the illusion of being more exotic. The reality, from what I've read about serval care, is more like having a two year old child that never grows up, with all of the loss of personal freedom that goes with that type of responsibility.
From a conservation perspective, serval ownership does absolutely nothing to protect the serval species. Serval breeders select the best natured animals for breeding pets, leading to servals that are a little more domesticated with each generation. In time, pet servals will be as different from wild servals as house cats are from wildcats.
If you are seeking furry companionship, consider adopting a shelter cat