1. A method for managing content, comprising: determining that a new or modified attribute is to be associated with future-created instances of an object type but not with at least some previously-created instances of the object type; and associating with the object type a default intra-type customization that associates the new or modified attribute with future-created instances of the object type in a manner that results in the new or modified attribute being stored in a database structure that is separate from a type-specific structure configured to store one or more type-based attributes common to both the at least some previously-created and future-created instances of the object type, wherein storing the new or modified attribute in the database structure that is separate from the type-specific structure results in the future-created instances being modified without affecting the at least some previously-created instances of the object type, wherein associating with the object type the default intra-type customization does not include modifying a definition associated with the object type.