I truly wish that I didn't have such sad news. I've learned today that Michael Bartosh has suddenly passed away. Michael was the co-author of the best Mac OS X Server book on the market, O'Reilly's "Essential Mac OS X Panther Server Administration" and was a tireless advocate for Mac OS X. Many, myself included, held him in awe for the amazing breadth of knowledge he possessed about Mac OS X and Mac OS X Server and his countless posts to the mailing lists that us Mac admins frequent.
I had the privilege of meeting Michael at an O'Reilly Mac OS X conference a few years ago and learned that he was also great fun to hang out with.
We're going to miss you Michael. Our deepest condolences to your family.
Note: John C. Welch has some nice commentary about Bartosh and his effect on our community.