TB-sized databases

Hi all,

I have a user who is looking to store 500+ GB of data in a database
(and when all the indexes and metadata are factored in, it's going to
be more like 3-4 TB). He is wondering how well PostgreSQL scales with
TB-sized databases and what can be done to help optimize them (mostly
hardware and config parameters, maybe a little advocacy). I can't
speak on that since I don't have any DBs approaching that size.

The other part of this puzzle is that he's torn between MS SQL Server
(running on Windows and unsupported by us) and PostgreSQL (running on
Linux...which we would fully support). If any of you have ideas of how
well PostgreSQL compares to SQL Server, especially in TB-sized
databases, that would be much appreciated.

We're running PG 8.2.5, by the way.

Peter