I've been tracking my reading and writing these reviews for 13 years now, and reading books like this reminds we why. I've read this before - but not since I starting writing, and I just had tantalising memories of reactions floating across, reminding me of a person I used to be.
Anyway, this ia great, luscious read, exploring the world of Istanbul, the world of medieval illustration and the challenging questions of progress, appropriation and hegemony.
There is also a murder mystery, which does work as a puzzle, but Pamuk doesn't really give you much reason to care about (you know the motive, just not the identity, and the cast of possibles are some of the least engaging characters - I much preferred the horse) and something I hesitate to call a love story, but which is a sensitively drawn marraige story at least. 
The whole is rich, sometimes verging on indulgent, but also replete with details. It evokes a time and place wonderfully, and allows you to sink into that other world for a while. Which right now, might be something we all need.