Hi!
Tormy: Well, cats are one of the basic features most users have an opinion about. They also have some unique rules tied to them (like adopting dwarves rather than the other way around). I mean, if you started a thread about "donkeys" or "muskoxes", I think you would probably run out of species-specific things to add.
And then there is of course the cat-lover and dog-lover divide :) :) :) :)
Doppel: Yes, you are actually pointing out the second problem with cats besides FPS: They kill cave spiders, so getting a silk industry up and running with a lot of cats can be something of a challenge (although, if you walled off an area regularly and opened it again only temporarily for harvesting, wouldn't that work?).
Silleh Boy: I think I see where you went wrong. :) :) :) :)
You had a very specific plan. It was so specific that the game/RNG simply couldn't resist and had to do everything it could to make you fail. But then again, we all enjoy epic fails as well (and not getting that guy to go berzerk at all is definitely epic, considering all the tantrumming you get without wanting it).
Lord Dullard: Earthquake Damage points out a good aspect I have always observed - cats end up patrolling the outside all the time and thus have a larger defense radius than chained animals (unless you want to do a lot of breeding and tying up) and a better activity cycle than owner-bound animals, given the bad habits of dwarves (if your military dwarves decide to go inside to have lunch, won't their dogs accompany them?).
However, this actually raises another interesting question:
Does vermin spawn infinitely or is there a danger of extinction as people claim for game? Quite obviously, if vermin went eventually extinct, cats may lose some of their efficiency in longer-standing fortress.
And I also wanted to ask something else. What kind of vermins are there in the nasty biomes people regularly go to? I mean, I always do normal forest/hill or good biomes, so I have birds, lizards, fairies and the like roaming the countryside and thus luring the kittens outside, but what about deserts, haunted areas, or glaciers? If there was an absence of outside vermin in the more "popular" biomes, I could see why people had the impression that cats never went outside...
Deathworks