Let me clarify my original post.
My friends are divided into Lists. Via the default Privacy Settings for the Wall (ie 'Posts by Me'), I can select which list of friends sees what is posted to my wall. When I update my FB Status I can also limit which lists of friends see my post to the wall on a post-by-post basis, via the 'Share' option's - custom privacy ("viewable to" or "Hide from").
It is this second option I wish to have WordPress feature - a 'Share' option that enables you to choose which List of Friends sees that WP post on the wall.
The 'Posts by Me' default privacy settings for "Viewable to" and "Hide from" for the Wall take precedence over an individual post's custom privacy settings. This is apparent when I choose to "make viewable" a post to a selective friend who is also on a default "Hide from" list. Even though I make the post "Viewable to" that particular friend, because he/she is on a default "Hide from" list, they do not even see the Wall tab let alone the post on the wall.
My work around right now, is to use the FB Notes app to bring in my WP Blog as an RSS feed. New WP posts are then seen in the Notes under the Notes tab. Because I can limit who can see my Notes tab, this is not a problem. I then have a second step in FB where I take that Note from the RSS feed and 'Share' it to my Wall, making it "Viewable to" the Lists I wish to see the WP blog.