Hi All,
Today I have had my head held hostage to cmake 
The problem is that in the new directory tree structure we have
pgrouting
core
common
doc
sql
blabla.sql
blabla2.sql
...
src
test
astar
doc
sql
foofoo.sql
foofoo2.sql
src
test
dijkstra
doc
sql
barbar.sql
src
test
...
And SOME of the core subfolders can be optionally build or not. Then for building an extension we would like to collect all the appropriate sql files and concatenate them into one large file that will get installed by the extension mechanism. The trick is getting cmake to bubble up what is happening in the local subdir cmake process to the master top level cmake process. Oh, and to complicate things cmake runs during the configuration phase, but you don't want it to install until you are in the "make install" phase.
Anyway, I think I have all the pieces I need to make this work. So I am in the process of editing and testing the process which has typos or bugs in it at the moment. So I hope to commit all this tomorrow if I can get it working.
Once that has been committed, I will take a pause on restructuring and migrate this all over to a windows build environment and make sure things work there. This will also give me a chance to test it with PG 9.2 and PostGIS 2.0 and eventually PostGIS 2.1.
-Steve