In a regular site the recommendations of Microsoft tells me not to store more than 200 GB in one SiteCollection in one Content Database.
But if I create a "Docment Center"-site I'm allowed to create an 'unlimited' site collection.
The only requirements listed, in order to be able use large (>200GB site collections), are the hardware specs and the skill level of the DBA. And the requirement for the 'Document Center' or 'Record Center' template.
SharePoint Server 2010 sites must be based on Document Center or Records Center site templates.
What makes the "Document Center" site template so special that unlimited sizing is allowed?
Is there a technical difference? Compared with a blank or teamsite?
Ref: http://technet.microsoft.com/en-us/library/cc262787(v=office.14).aspx#ContentDB