Meerkats are exceptionally popular due to massive popularity of the film The Lion King and the later success of the Animal Planet show Meerkat Manor, a documentary highlighting the daily lives of the social animals.
Meerkats are rather drably colored but probably appeal to humans because of their ability to stand like a person when they are on the lookout for predators. This simple characteristic has given them a perceived charisma among humans and the interest in them as pets has understandably increased.
Meerkats are small animals, and they have the word 'cat' in their name which may be deceptive to the true nature of these colonial carnivores.
Meerkats are not cats (obviously). It should be understood that meerkats are not cat-like nor do they possess common 'domesticated traits.
Meerkats are social mongooses. Meerkats belong to the family Herpestidae and the order carnivora, which includes moongooses and kusimanse. They are more closely related to mustelids and vivivverids. Once meerkats are understood to be mongooses their behavior in captivity starts to make more sense. Actually, other mongoose species may make better pets.