Will upgrading Ubuntu 9.04 --> 9.10 update Mythbackend?

[david-8uUts6sDVDvs2Lz0fTdYFQ at public.gmane.org (David Kramer)]

I built a new Mythfrontend box to hook up to the TV in my living room
last month.  At first I installed Ubuntu 9.10, but found that 9.10 had a
newer version of Mythtv that was incompatible with the version that
comes with 9.04.  I know, Myth versions come out so often ;)  That means
I have to upgrade all machines at once (the server, my laptop, and the
new living room computer).

I usually shy away from version upgrades due to so many failed ones from
years ago, but my last Ubuntu one went pretty smoothly.  My question is
this: if I upgrade my server from 9.04 to 9.10, will the installation of
the new Mythtv-backend version automatically migrate the DB schema to
the new version, or will I start screaming for hours on end with
withdrawal symptoms until I get it fixed?

OK, so I have another question.  I lied.
I installed 64-bit Ubuntu on my server.  I kinda regret it, because
there are a few things that *still* don't work in 64-bit, like the
software for my LightScribe burner software.  It's not the end of the
world if I can't but is there a way to go from 64 bit to 32 bit without
wiping everything out?

Thanks.