Twitter has been doing #4 aggressively as well, which is a bit disappointing, since somehow I assumed they were better about netiquette than LinkedIn is.
Twitter is horrible at that. Every few weeks they add a new notification type that you have to unsubscribe from, lest you get hit with another "newsletter" every few hours.
3. I shouldn't have to sign in to unsubscribe.
4. Don't auto-subscribe me to new notification types. (We're ALL looking at YOU LinkedIn.)