pg_dump - schema diff compatibility

Looking at the mailing list archive, this is just one in a rather long
line of questions regarding diffing db schema dumps, but I've been
unable to find what I was looking for in any of the prior
conversations. I know of apgdiff (seems to work very nicely) and of
other specialized pg diff tools (as outdated or proprietary as they
may be), but what I'm interested in is just a plain, basic schema dump
with a database object order usable with diff.
I can't find it now, but I'm fairly certain I've read somewhere (in
the release changes of an 8.x pgsql version?) that pg_dump has been
"upgraded" so that it orders database objects fist by their
dependencies and then by name. I thought that would imply that dumping
the database like so
pg_dump -f out.sql -F p -s a_db
would give me an sql script which I could compare versions of with
plain old diff or svn diff or whatever existing diff tool I care to
use.

I guess my question is: is pg_dump supposed to dump the schema in a
diff-compatible, predictable way but it's not working or is pg_dump
only concerned with satisfying db object dependencies?
I would very much like this functionality because it would make pgsql
much better integrated into the work environment we have setup at the
office (using e.g. svn diff would be very nice). Tools like apgdiff
don't help as much: it great that it's command line (can be
automated), it does it job well, but it sitll only tells me e.g. that
a view is different, rather than showing me _how_ it is different or
allowing me to compare object definitions using a generic diff - which
is what I really want.

Sorry for the confusing trail of thought and thanks for any comments,
t.n.a.