Multiarch in Oneiric for developers

[David Henningsson]

On 2011-08-16 20:46, Steve Langasek wrote:
> Dear developers,
>
> As part of the work to eliminate ia32-libs in favor of multiarch library
> installation
> (https://blueprints.launchpad.net/ubuntu/+spec/foundations-o-multiarch-next-steps),
> i386 sources have been enabled by default on amd64 systems in oneiric.  For
> new installs, this is done by default in alpha-3 and above; and as of today,
> update-manager also ensures that i386 multiarch support is enabled by
> default on upgrade from natty.

I'm sure this is all great and something many people have been waited 
eagerly for, but for my own part I must say I have missed the newbie 
introduction wiki/blog, or "Multiarch for dummies". [1]

I'm looking for answers to things like:

1) If I'm an Ubuntu end user who likes to watch youtube videos, what 
does multiarch mean to me and what advantages will I notice?

2) As I understand Multiarch is a way to run i386 binaries on an amd64 
system. [2] What are the typical i386 binaries you want to run on amd64?

3) If I'm a packager of a random library, does multiarch affect my 
packaging? Is there anything I should be aware of or should it "just 
work"? (What if I use debhelper 7, or cdbs, etc?)

-- 
David Henningsson, Canonical Ltd.
http://launchpad.net/~diwic

[1] I read through http://wiki.debian.org/Multiarch but that was mostly 
about how, rather than why.

[2] And it helps cross compiling, but let's assume I'm not interested in 
that right now.