Expand support for Saved Queries

A feature common to a number of ECM systems is the ability to save a query for later use. This allows for the building of a logical view different to that of the underlying folder structure. It is possible, and likely, that client software will implement this, is it desirable that it be persisted to the repository so that different clients can share the same set of saved queries? Additionally it may be desirable to support parameterized queries, effectively allowing for search templates.
Some questions:
• How many repositories support saved queries?
• What are the potential implications for each binding?
• Would 'Query' objects be first class CMIS objects, e.g.: ACL applied, queryable, have subtypes etc?