A new feature of SharePoint 2010 allows you to publish your content types from one central hub to Site Collections that choose to subscribe to them.
The first thing you need to do is to to define the location of your hub. You will find this in the properties of the managed metadata service at the bottom:
Then in the properties of the managed metadata service connection you need to tell it to “consume content types from the content type gallery”:
The site collections that are then supposed to use the content type hub will need to activate the site collection feature “Content Type Syndication Hub”.
In order for content types to be published you need to change the setting under “Manage Publishing for this Content Type”