Very true for low-level system libraries, but applications should really not waste energy on trying to be OOM-safe: it's hard to understand which actions are safe when you no longer can allocate memory (releasing resources often requires allocating memory temporarily), and it just adds complexity which basically will never get tested, thus getting broken quickly and gaining nothing over just crashing on a NULL dereference.

See the experience of the D-Bus (which tries hard to be OOM-safe) on this topic: http://blog.ometer.com/2008/02/04/out-of-memory-handling-d-b...