This feature has been implemented in release 1.3.0
track more information about your products or customers
This feature will let you add custom fields to standard records such as products, categories or customers. For example, you can create new field on categories containing google taxonomy id. Or field on products containing amazon SKU identifier.
These fields can contain values, but they can also be used to reference other records. You can create custom field on product that references other product(s). This will allow you to define new relationships between records (similar products, featured products, etc)
Beside custom fields, you will be able to create brand new records and reference them from standard records.
These custom fields and custom records will be automatically available when creating lists / xml
The primary use case is customization. You can easily extend your prestashop database to exactly match your needs.