1) There should be one schema per Liferay instance. It should contain the stuff required to operate Liferay the application and no more.
2) There should be another schema for each portal instance (ala the control panel) with a unique identifier. In my case, that would be:
www.website.com
www.mydomain.com
www.blinkythings.com
www.roundthings.com
Splitting this up in to things that are application-wide in a given Liferay instance and for each virtual host should allow for enormous flexibility and portability (ability to move from one physical host to another). It would also make it easier to set up settings that were unique to a given portal instance.
