I wonder who that other person could be? Anyway, as for the specialties, there are almost as many specialties in vet med as in human. The two most difficult to land are ophthalmology and surgery. The optho is due to a lack of positions and not a great a demand. The surgery is also slightly a lack of spots but mainly because there are so many applicants for those positions. Therefore, you need to be in the top of you class and have some EC activities. This is no different than if you wanted to get a Derm of Rad residency in human medicine. I am unsure about many of the other specialties, but I know an exotics is the MOST difficult to attain. The test is so difficult that I believe less than 100 people in the world have it. However, if were really interested in exotics, you could simply work in a practice that catered to exotics. Do you have a specialty in mind? Have you applied already? What type of human medicine are you interested in doing?
I don't think that residency programs are only for the top notch vet students. The great thing about vet medicine is that you don't have to do an internship or residency program to practice medicine. If you want to specialize, then you can, but you don't have to. In fact, there are a lot of pros and cons to doing each side. There isn't any specialty in "dogs" though, so I'm not sure exactly what you are looking for, and every vet school in the US has a general curriculum where you will learn about all species (dog, cat, horse, cow, pig, sheep, goat, birds, plus more) and that will never change until the National Board Exams change. Some schools offer tracking in certain areas (such as small animal, large animal, equine, exotics) but that depends. You can become board certified in Feline Practice and only work on cats, and I"m sure if you wanted to only work on dogs you would be able to. I think that a lot of students go on to do internships, but a much smaller percentage of those students go on to do a residency. Internships seem to be in vogue now, at least at my vet school. It's not a given that you will match, but if you put the work in, it will happen. Also, what you want now, may be very different that what you want after being in school. Specialization in vet med is a lot different than human med and you need to see all sides of it. I've seen it in vet schools and private practices and I've worked in regular DVM non-speciality practices and like I said, there's pros and cons to each.
Neurology, Dermatology, and Cardiology are all subspecialties of small animal internal medicine. So after your small animal internal medicine residency you do more training in usually one of those specialties.
Dermatology isn't a subspecialty of medicine in vet med. neuro, cardio, oncology- yes. But derm has it's own program.
The way it works (by my understanding from working at the AMC) is that if you want be a vet neurologist (for example) you do a 1 year internship, you do a veterinary neurology residency for about 2 years, you take the internal medicine general board exam (along with all the other people who are in IM resdiencies, neuro residencies, onc residencies, cardio residencies, both small animal and large animal) The general Im exam covers general medicine and physiology of all species. Then you either finish your residency for one more year (if it's a three year one) or you work for one year in your field (neuro, onc, medicine etc.) and then you take your specialty board exam at the end of that year.
It's quite rigorous and the exams are only offered once per year at the ACVIM conference. But neurologists don't have to complete an IM residency before taking the neuro boards, there are about 5 neuro-residency programs in the US. This also means that IM specialists have to pass two board exams to be "boarded", the general exam and the specialty exam. At my vet school (and at places I've worked before) we also have cardio residents, neuro residents, and onc residents, and they are not IM boarded.
I'm not exactly sure what's on the general exam, but I know it covers "general physiology" and that you memorize Cunningham and Guyton for it basically. I would imagine general phys might cover all the species and the way the person made it seem was that the SA people sit for the general exam along with the LA people. The specialty exam (SA Med, LA med, cardio, neruo, onc) is different though. He said for that one, for SA med you memorize Ettinger... Sheesh!