I don't really like that he puts tracking javascript in his addons. Take a look at the source of this Facebook Disconnect addon, its at the bottom. Why don't people just write a simple bash script that toggles blocks for the facebook domains in the hosts file?
I'm sorry I was wrong. The file that the install button does not link to the addon like the Firefox addon site does, so saving the link is not the addon. I apologize.
Edit: I'm sorry guys, I guess the file that the install button links to is not the addon itself like the Firefox addon site does, so saving it does not give you the addon. I'm retarded. He does not have tracking cookies, I apologize.