hey looks great!!!
I've posted it in the playground wiki, so if you want to modify the details and
expecially add some information, please do so! 
http://www.arduino.cc/playground/Learning/Tutorials
the wiki is the special repository for all this kind of usefull resources...
they might get lost or be difficult to find again in the thousands of forum posts.
to subscribe go here Arduino Playground - LoginForm
for now the tutorial links to your page, but It would be great if you could add something to the Arduino Wiki
some introductory information for newbies...
I would add something like:
- links to "what is ZigBee" from wikipedia Zigbee - Wikipedia
- why did you choose ZigBee?
- why do you think is better than other wireless technologies?
etc...
but your contribution is already great!
merci beacoup
b.
ps. please add yourself and your site to the people's list of Arduino users
http://www.arduino.cc/playground/Main/People