@Youknowwho4eva, you called?!
Today, there are two types of lists: Favorites and Custom. When a user clicks <Favorite> on a product page, the product automatically goes into his/her Favorites list. Other products get added to Custom lists when a user clicks <Add to list> and selects the particular list to which he/she wants the product added. Favorites lists are system-generated; every user gets one. Custom lists are created by users at their whim. The privacy setting of both types can be toggled from private and public.
As a public marketplace, we can derive great value for our shop owners about how their products are doing: how much they are selling, how much they're being seen, how much they're being interacted with by others. Favorites are one of the ways we can understand this interaction and we consider the act of Favorite-ing to be a public act.
However, some users have chosen to set their Favorites list as Private. In these cases, we lose the ability for our shop owners to understand interaction when those interactions are happening privately.
So, we are going to be making a site change after this week that prevents the Favorites lists from being able to be set as private. Nothing is happening with other kinds of lists. Custom lists will still be able to be set as private.
For the users who currently have a private Favorites lists, we won't be suddenly revealing their contents to the public. We will be preserving those lists under a new name, and the lists will still be private.
We sent out advance notification email only to users who 1) currently have a private Favorites list with ? 1 product in it; and 2) currently are subscribed to receive emails from us. It's a rather small population and that's why we didn't send the advance notification email to everyone or message it previously on the forums.
I hope that helps clear up any confusion about what we're doing and why.