PostgreSQL 9.0 or 9.1 ?

Hello,
we have been running our infrastructure on 8.3 for quite some years now,
and i am thinking it is now time to upgrade all major parts of our system
(java, jboss, postgresql).

I would tend to be a little "radical" and go a little optimistic and greedy about it.
I have been using 9.0 as a test system with no major flaws for quite some time as well.

Till the end of July i must have finished all the migration to the new versions.

The migration will involve testing of about 5,458 sql statements and the

migration of some heavily customized in house functions, including

a version of DBmirror (which is in use for a very specific set of problems)

So i am asking what would be better by your perspective to do?
Go for 9.1? or stick to 9.0?

Where is a stable (release) version of 9.1 be available?

Has any one faced any issues migrating from 9.0 to 9.1

Achilleas Mantzios