I haven't had the chance to read through everyone's post here (pressed for time), so excuse me if I'm just repeating what's already been said:

I think that declawing cats is terrible. You can clip cat's claws, you can train cats, and there's probably even more alternatives than that. What's even worse, is when people DO get their cats declawed, and they take out both the front AND back claws, so if the cat does get into a fight with another cat, it has no way of defending itself unless it can get the chance to bite. Someday, I hope to be a veterinarian, and that's probably a procedure that I will not be performing, or, I hope that I'll have that choice.

As far as spaying and neutering goes, I don't find that a terrible thing like declawing, but unless you plan on breeding your cat, it's probably neccessary.