[YourMatt]

Facebook's implementation is only behind two clicks. When you go to add a post, there's a drop-down to select who you want to see it. Opening the drop-down is one click. Selecting the list is the other one.

The problem is in managing the people in these lists. I haven't found a place where it shows all users I have in a single list. Adding or removing a single user is easy though, as the available lists are available for selection/deselection anywhere you're allowed to change your friend status with that person.