I agree that this does give maximum flexibility, but it also defers a maintenance headache onto the facebook administration.
I have to ensure that:
1) all of my blog authors have facebook accounts
2) That I make them admins of my page
3) That they then configure their 'publicize'

Considering that some of my contributors are not too IT literate, or actively avoid Facebook, this does not really work for me, and increases the pain for adding new users.

The alternate option, is that I go into each post, and separately set the 'publicize' option.

The publicize option is useful, but some improved handling here would be appreciated.

Per Blog and Per User
For maximum flexibility, these connections between WordPress.com and our Publicize services are per blog and per user. If you have several blogs you want to connect, you’ll need to connect each one separately. For multi-author blogs, each user that wants to connect to a Publicize service will need to do so separately as well. http://en.support.wordpress.com/publicize/#per-blog-and-per-user

I have linked the blog to my Facebook page for Southmarston, and for blog posts that I make, they appear directly on the Facebook page.

However I have other users who also post to the Blog, but their posts do not automatically go to Facebook.

What is the blockage here?
Do they need facebook credentials, and be given facebook admin privileges for the page (which they don't currently),
or
Can they simply select the Facebook option under the Publicize section on the post editor, and the post gets uploaded with the credentials that I have provided into the blog config?

By default it seems that the facebook option is not enabled for all of my authors. Do I need to explicitly tell them to enable publicize for their new posts, or is there a way that I can configure it for them, as a blog-wide setting?