Good article, it explains  very clear which are the main problems of analog layout and how must be the solution. The only sad thing for me is that  I must hurry to get the Phd or at the lab I will be obsolete as "layout man"...

Hi, reading this article from 5/17/2007 now - 2012 - I think not much has changed at all!!!
For most non-trivial circuits, like having 40 transistors most autoplacer fail, although a good designer can find a solution quickly. The constraint concept ends up with adding more and more constraints, till you have no overview anymore or run into over-constraintment or tool problems!
Take a look at "Deterministic Analog Circuit Placement using Hierarchically Bounded Enumeration and Enhanced Shape Functions", 2010. This paper describes an advanced placer, but the created layout would NEVER survice a real-world design review  :'(.
It seems that our PhD workers like to create new and more algorithms, but not even have criteria or benchmark to decide what a good layout is!

Bye Stephan