Here's a personal anecdote to illustrate the uphill battle here.
Tonight I was talking to a friend of mine, a friend who I know visits my site religiously, 5 - 10 times a day.
He IM'd me and said, "Hey have you heard about this new +1 thing Google is doing? I heard about it on the radio. You should add that to your site."
To which I responded, "I've had the +1 button on my site for a month now!"
To which he responded, "Oh is that what that is? I saw it, but didn't know what it was for."