How's the Xmega port going ?
I got my Xplain board up and running using LUFA. That went pretty smoothly on Windows. Can now do USB PDI programming from AVR Studio which is kinda nice (JTAG box not required).
There doesn't seem to be many examples of Xmega code out there other than the Atmel app notes. Which are all little pieces. I'm working on the ADC example but it is complicated by so many different ways to do it. And trying to write the data to the SRAM (64K pointers only ?)
I used code from frankvh to implement printf() on the Xmega to start with. I forgot how useful printf() is but also remember the confusion when I first tried to use it. This is not much code to implement it.
http://blog.frankvh.com/2009/11/14/atmel-xmega-printf-howto/
Let us know as you get parts of the port to work.