XS Core and Contrib
The potential of the XS is enormous, and the effort required to realize it is gigantic too.By definition, any single team will bottleneck the development.
The XS team @ OLPC will focus on a core set of facilities that we consider of critical importance. This does not mean that other things are not important or worthwhile -- it means we have not had time to work on them all (yet!).
There is a huge green field out there of things we would love to be doing. We will do our best to open the doors to all contributors.
If you can jump in, familiarize yourself with the XS infrastructure, current state of things, the roadmap, and draft a plan that helps get something implemented -- fantastic! Post in the server-devel mailing list, and join the fray. You must be able to be self-sufficient and do the job yourself though!
An interesting document to read before you post to the list is Moodle's "Working with the Community" document which borrows heavily from a similar one that the Linux Kernel crowd uses.
Packaging
The mode of building the XS is with packages, so you will want to package your code/configuration in RPM packages.