I've been a G+ user since the beginning (July 6th, 2011 to be exact) and one feature that i would love to have is the ability to mute or disable +1 notifications without muting the comments. Don't get me wrong, I love seeing the activity on my posts and an thrilled when you give me your click of approval, but some posts start to run away from me and offer little value to the conversation or even to the G+ experience.
I can only imagine how bad it must be for those famous users who get tons of mindless +1s with every post the write. I don't know what technique they use to maintain their sanity but this simple feature would be a welcome addition and seems easy enough to implement.