Partitioning / Clustering

What is the status of Postgres support for any sort of multi-machine
scaling support? What are you meant to do once you've upgraded your
box and tuned the conf files as much as you can? But your query load
is just too high for a single machine?

Upgrading stock Dell boxes (I know we could be using better machines,
but I am trying to tackle the real issue) is not a hugely price
efficient way of getting extra performance, nor particularly scalable
in the long term.

So, when/is PG meant to be getting a decent partitioning system?
MySQL is getting one (eventually) which is apparently meant to be
similiar to Oracle's according to the docs. Clusgres does not appear
to be widely/or at all used, and info on it seems pretty thin on the
ground, so I am
not too keen on going with that. Is the real solution to multi-
machine partitioning (as in, not like MySQLs MERGE tables) on
PostgreSQL actually doing it in our application API? This seems like
a less than perfect solution once we want to add redundancy and
things into the mix.