OSDI (2nd) was written in 1997, perhaps you were thinking of this? http://www.amazon.com/Modern-Operating-Systems-3rd-GOAL/dp/0...

Minix 3 is a whole different ball game though. It's an interesting kernel with some interesting ideas, but I still recommend Linux as it's both more popular and reflects the majority of UNIX design decisions today. Even the OSs with praise for microkernel design tend to incorporate a number of monolithic features.

EDIT: Sorry! I had no idea there was a Third Edition of OSDI out http://www.pearsonhighered.com/educator/academic/product/0,,.... However, I should mention that I meant those Linux books to be read in conjunction with the kernel code -- the book is still valid today despite the additions to the kernel in the past couple years.

The 3rd edition of OSDI is definitely worth reading. The MINIX3 kernel is only 4000 lines of code; very clean, and easy to wrap your head around.