my cats are both rescues, and both were old kittens/young adults when i got them. we (my vet and i) did shots each year for the first three years, then a booster three years after that and now they probably won't get anymore. they are indoor cats so they have minimal exposure to anything and one of my cats had a severe reaction to her last vaccination. cats can actually get vaccination induced tumors (rare but it happens) adn i decided in their case, it not worth the risk.
as for dogs, i tend to lean towards fewer vaccinations as they get older, with the exception fo rabbies. its not that i think they will get rabies but i live in a large metro area and its required by law. i would rather expose them the the minor risk from the vaccination than the test for rabies if it were to ever become an issue.
as a word of warning to everyone....if you have rabies laws in your area and the vet offers a 2 or 3 year shot, check the laws. some areas laws are not yet updatd to allow the multiple year shots a "valid" if there was an issue. also, a friend of mine worked in a vet clinic and at her clinic the three year shot adn the one year shot came from the same vial. just an fyi.
"Not all who wander are lost." J.R.R. Tolkien