There's one more privacy feature/annoyance with photos on Google Plus. Apparently when I share an album with someone, that person in turn can share that album with other people and can also see who else I've shared it with. Now what's the point of a private album if everyone else can share my album. I like how Facebook solves this problem. You, as the album owner get to choose who sees the album. People who you've set the visibility as true cannot see who else I've shared it with.