Threewp Broadcast is a network content syndication plugin for WordPress by edward_plainview, that allows you to automatically share content by multiposting between multisite blogs.
Syndicate posts to other blogs, update posts between blogs, share content templates, etc. Broadcasted posts can be linked to their parents, which updates child posts when the parent post is updated. This includes all data: title, slug, content, custom fields, attachments, etc.
Posts, pages, custom post types
Taxonomies (categories, tags, etc)
Custom field blacklist, whitelist, and protect list.
User role access granularity
CDN support (nominally tested Amazon S3)
There are several Broadcast plugin packs that expand the capabilities of Broadcast.
More info: https://en-gb.wordpress.org/plugins/threewp-broadcast/