Yes it uses PC architecture, but not necessarily the PCs Qt-Libs.
On my setup it uses the libs provided by QtCreator.
The point is, why can I compile the same project
(with the same .pro file with
CONFIG += mobility
MOBILITY += gallery)
for the Qt Simulator target
but not for the Maemo target?

For example, both envirionments have the qmobilityglobal.h header file:
./Simulator/QtMobility/gcc/include/QtMobility/qmobilityglobal.h
./Maemo/4.6.2/sysroots/fremantle-arm-sysroot-20.2010.36-2-slim/usr/include/qmobilityglobal.h
But qdocumentgallery.h is only in the Simulator envirionment:
./Simulator/QtMobility/gcc/include/QtGallery/qdocumentgallery.h

What is the point in having a "simulator" environment without
a matching "real" environment?