I have a collection of PUBLIC FACING and BACKOFFICE drupal sites.
There are about 6 PUBLIC facing web sites.
There are about 10 BACKOFFICE sites ( non public facing)

The backoffice sites specialize in a specific kind of data. an example would be movie listing nation wide.

I am looking for a solution where the PUBLIC sites will be able to display views from the BACKOFFICE sites.

I am thinking of two options:
a... use the views system on the BACKOFFICE drupal sites, and expose it as a block on the public sites. perhaps still being able to pass a parameter to the view from the PUBLIC sites.

b... use views on the PUBLIC sites.

I was thinking of just using FEEDS from the BACKOFFICE sites to the PUBLIC sites. But it would be nice to have a single master database.

Are there any other interesting strategies in DRUPAL 7?
multi-city. but I have a common set of articles, calendar, comments that I want to display on a subset of the sites.
some strategies would be interesting.