Developer Transition Kit
http://developer.apple.com/transitionkit.html

The Developer Transition Kit brings together all the components you need to
create Universal Binaries that run on Macintosh computers using Intel
microprocessors. The Kit contains the information, sample code, software,
and hardware you'll need to develop a Universal Binary.

* Universal Binary Programming Guidelines
The Programming Guidelines cover all the Universal Binary, Xcode and Intel
topics you'll need to know. It guides you through the straightforward steps
needed to create a Universal Binary and optimize it.

* Universal Binary Sample Code
This folder of Universal Binary sample code contains a representative
sampling of all Mac OS X programming topics and demonstrates the simple
steps needed to ensure Universal Binary compatibility. Browse through the
samples to see the Universal Binary Guidelines ideas brought to life.

* Developer Technical Support
You'll have access to Apple's Developer Support Engineers to support your
development with the Developer Transition Kit.

* Use of a Developer Transition System
This development system allows you to create Universal Binaries and
validate and verify that your application runs on Macintosh computers using
Intel microprocessors. This Developer Transition System includes:

* Mac OS X
The development system has the preview release of Mac OS X Tiger on Intel
pre-installed, allowing you to run, verify, and debug your Universal Binary
application.

* Xcode 2.1
The development system comes pre-loaded with Xcode 2.1. Xcode 2.1 is the
development environment for creating Universal Binaries. Updates and
additional downloads of Xcode 2.1 will be made available as needed for
Transition Kit developers.

The combination of the Developer Transition System, the Universal Binary
Programming Guidelines, the Sample Code, and Developer Technical Support
gives you everything you need to move your application to the Universal
Binary Format.