The family thing is typically good for causing some contention in the tribe. It seems to be the one reward people get the most upset about if they don't get chosen, which is always strange to me. Maybe I'm not as close to my family as some of the players or maybe I just don't understand the strong desire they have after a few weeks of playing a game to have some genuine conversation, but I've always just looked at it with the point of view of, "Man, these people are going to be home in like 15 days and will get all the family time they want."
But, anyways, in the past, the reward has been a good way of breaking up alliances or tossing one person on the chopping block who might otherwise have previously been safe. It's just that this season, we saw none of that since the person who got to decide is not even in the game technically and, thus, no real drama resulted from family week. For some odd reason, the producers really haven't appeared to have much desire to throw wrenches in alliances like they have in the past.