Automatic index advisor?

Hi,

I'm writing a book on SQL, with a short section about query tuning and
automatic optimization advisors for different RDBMS platforms, for
instance, extensions to EXPLAIN that recommend new indexes based on
workload and query plans.

When I searched for a solution for PostgreSQL, Gurjeet Singh's name
came up as the designer of an index adviser patch for PG.  But the
latest information I found was in 2007.

There's also a project at pgFoundry, but it's listed as in a planning
stage, and there are no releases.

Can I ask what's the status of this capability for PostgreSQL?  Has it
become part of PostgreSQL 8.x or 9.0?  I couldn't find any information
in the docs.  Is there any value-add tool for EnterpriseDB?

If Gurjeet's patch is still under development, are there any other
tools currently available for PostgreSQL that provide this kind of
capability?

Regards,
Bill Karwin