The one I've been most involved with was "disabled".

The point made by the disabled people that I was working with was that "people with disabilities" was about being recognised as a person first, then as a person with a disability. Those that wanted to be called "disabled" saw themselves as disabled from society by virtue of having a disability as well as because of their specific disability.

I think that the biggest difference is who has put forward the new word - the people to whom the word would apply or others (perhaps wishing to create a euphemism). Use of the word "disabled" has been accompanied by a whole movement towards "disabled people" taking more control of their lives and being more active on committees and in charities. No more "does he take sugar".

It is such a personal subject I'm sure others will disagree.