For me, one question answers this question: would YOU want a seeing eye cat?
Hello, MOLLYBIRD, and welcome to the Straight Dope. It’s hard to tell if your question was intended to elicit factual answers, and therefore does belong in this forum, or if you were merely making a poll, in which case you’ll probably get the kind of replies you’re looking for in the In My Humble Opinion forum.
However, if you are, indeed, searching for a factual answer, the Master himself has addressed this very question, here: http://www.straightdope.com/classics/a1_005.html, which begins:
If you take issue with his position in this column, you might want to post a discussion about it in the Comments on Cecil’s Columns forum.
To repeat myself.
A dog will go fetch a newspaper in the pissing rain, a newspaper it can’t read.
Try teaching a cat to do that.
Which is more intelligent…nuff said
And, of course, you can never harness seven cats to a sled and expect them to pull it all day either.
I suspect we’d have no disagreement, however, as to which is the more intelligent - dog owners or cat owners. 
Um, obedience != intellgence.
Cats can learn quite a bit. I’ve had cats that learned to use the toliet (that cat figured that one out by itself), open closed bedroom doors (though it had to have the right kind of handle on the door) and more than one who showed pretty amazing understanding of spatial relations.
Slee
Intelligence? “oh look it’s pissing down I’ll go get the paper which I can’t read,Gee I sure am well trained, bet the cats jealous or will be when he wakes up”
You couldn’t train my SIL to do that stuff either but that doesn’t mean that she is smarter than a dog. Cats simply have personality issues that we often associate with disfunctional yet smart people. They aren’t. Cats are simply manipulative and sociopathic mammals and that is the whole story.
We haven’t even figured out how to agree on deciding whether one *person * is smarter than another, much less compare across species.
Cats are independent hunters, and dogs are pack animals, and this explains a lot about their respective “cultures” and behavior. An attempt to gauge intelligence of dogs vs. cats smacks of anthropomorphism.
Aye, but the dog is thinking* “I’ll get a bit wet, but I’ll please everyone and I’ll get dried anyway and I get free food and allowed to lie on the couch in the warm and get petted and biscuits and ooh television - great! Woof!”. That doesn’t strike me as stupid behaviour.
- for a particular value of “thinking”, of course.
I’ve never seen a service cat for the blind, a police cat, or a watch cat. On second thought, it appears cats might be a little smarter.
Apparenty, cats can’t hold down a job!
Meanwhile, the cat is thinking “I’ll stay nice and dry and comfortable, and still please everyone and get free food and allowed to lie on the couch and get petted anyway. Purr.”
And the cat gets pretty much the same rewards without expending any energy
“Look I’d love to help - but there’s some important sleeping I’ve got to do”
Plus, cats can operate pneumatic drills
Dogs are far more trainable. They do a lot more for humans. Most dogs want to make humans happy. We have bred breeds that show remarkable abilities to understand a huge number of commands* and to be problem solvers*.
If there was an IQ test for animals, I am sure dogs could be trained to do great at it.
All that said cats seem to have us trained very well. Cats are acknowledged as being the most varied predators on land. They can and will hunt and eat nearly any other creature. Cats are good problem solvers.
I would say actual intelligence is a toss, but a smart dog is far more trainable than the best breed of cat. Trainability does not equal intelligent, but it is a useful indicator when we have so little to go with.
Jim
- The Border Collie
I keep my couch flush to the wall - just in case.
And that’s a sign of species smarts too. I defended our canine chums, but let’s face it who the hell is in charge of this relationship?
Yes, only a truly stupid animal would run out in the pissing rain and a really smart one would send their owner out to get his own paper 
Dogs are pack animals as as such serve the collective, cats are designed to be solitary animals. So the ability to train one is not a good indication.
I would think that one way to measure intelligence would be language skills.
Dogs, in my experience, do learn their name, along with other key words and phrases (i.e. “biscuit”; “outside”; “bath”). My dad’s dog learned that, after dad came home from work, there were cocktails (why, yes, my dad is a functional alcoholic. Big woop, wanna fight about it?). Cocktails included a jerky treat for the dog. It got to the point where my dad and his wife had to start calling then “C O C’s”, since the dog got excited and barked whenever “cocktail” was mentioned.
Cats, I presume, do learn their name (although they’d never admit it). But do they have as good a grasp on the language as dogs? Honestly, I don’t know the answer, but I do know that there are lots of Dopers with practical cat experience.
That cats do not serve these functions may have nothing to do with intelligence. Cats are much smaller than your average service dog, and would more likely trip a blind person rather than lead them around potholes or across the street. Their smaller size also makes them less effective guards. Also, humans don’t associate a cat’s vocalizing with warning like we do a dog’s barking.