I believe cats can get it, but it's rare. And, unless your pet is elderly or immune-compromised, kennel cough is a minor issue and there's really nothing vets can do for it anyway, so there's no point in going to the vet at all (unless the pet develops a secondary bacterial infection).
I think that generally it's not very serious for them. HOWEVER, some studies (mostly shelter medicine articles) have been saying that there has been an increased incidence of Bordetella in cats. There is actually an intranasal vaccine for cats now. The concern is that if they contract kennel cough in conjunction with another upper respiratory virus, it can lead to some very serious complication like pneumonia, especially in kittens, older cats, immune compromised etc. We saw this in the winter at the shelter where I volunteer. One of my foster kittens got pneumonia, and my vet and I both think that Bordetella was probably a factor.