These two items are complete in 8.2, IIRC
Allow constraint_exclusion to work for UNIONs like it does for
inheritance, allow it to work for UPDATE and DELETE statements, and
allow it to be used for all statements with little performance impact
Fix memory leak from exceptions
http://archives.postgresql.org/pgsql-performance/2006-06/msg00305.php
This item was rejected by Tom, since a workaround exists
Add estimated_count(*) to return an estimate of COUNT(*)
This would use the planner ANALYZE statistics to return an estimated
count. http://archives.postgresql.org/pgsql-hackers/2005-11/msg00943.php
-- Simon Riggs EnterpriseDB http://www.enterprisedb.com