We are still using PostgreSQL 8.2.4. We are running a 24x7 system and database size is over 200Gb so upgrade is not an easy decision!
I have it in my plans so in next few months I will setup new servers and upgrade to version 9.
Everything changed, performance-wise, in 8.3, and there have also been improvements since then too. So rather than completely changing your database platform, at least take a look at what work has gone into Postgres since the version you're using. http://www.postgresql.org/docs/8.3/static/release-8-3.html#AEN87319
-- Thom Brown Twitter: @darkixion IRC (freenode): dark_ixion Registered Linux user: #516935
