There's already work underway to resurrect LDAP authentication. It won't use the built-in Oracle hooks because it needs to work for both PostgreSQL and Oracle. You can e-mail Lars at Collaboraid for more details.
Categorization ... there's some categorization stuff available already in the content repository and there's work underway do do a more general categorization package, check the recent thread in regard to this. Folks should organize and work together if possible, though I realize client deadlines can make this hard or impossible to do. There's no reason to duplicate effort if we can avoid it, and general categorization is badly needed.
