What is this new Friends list thing?
This is for members of Renderosity that you consider your "online" friends. Its an easy way to keep up with them and to get quickly to their Homepage to contact them via Sitemail.
Its different to "Favorite Artists" as that feature is for artists whose work you want to keep up with by getting ebots when they upload a new image. This might not be necessarily someone you communicate with or consider an "online" friend.