I have written a draft of a revisited compile guide.
The old one is a bit out of date. The draft introduces CMake (for osg, simgear, and flightgear), the ccmake gui, using "out-of-source" builds, a custom prefix, and avoids using root.
I think that the end result is a pretty typical dev installation, but I wanted to run it by others before I replace the old one.
If anyone finds something that needs to change, reply here or on the wiki. The draft is on my user page.
Original:
http://wiki.flightgear.org/Building_FlightGear_-_Linux#Compiling
Draft:
http://wiki.flightgear.org/User:Daemonburrito/Building_FlightGear_-_Linux