Metadata is where its at.
Storing Petabytes of data is no longer the issue - its all about the metadata. Otherwise you will have a warehouse full of objects and if you haven't classified them very well - no way find them. It would be interesting once you start analyzing the data if the objects will lose some of its value fairly quickly.
You will need a separate database - non of the vendors I have seen have given enough thought to this and using a CMS with proprietary classification methods is a sure way of painting yourself into a corner. Having to change horses with Petabytes of objects in tow will be a nightmare.
Object life cycle management is also something that needs addressing - some objects have a limited rack life - how do we approach that and what metadata do we keep once the object is destroyed.