The Symbian platform related documentation as part of Qt reference docs are outdated.

Symbian related Qt installation page (http://doc.qt.nokia.com/4.7-snapshot/install-symbian.html)

• should mention that in most latest Symbian devices Qt is preinstalled as follows:

• Symbian^3 and Symbian Anna devices have Qt, Qt Mobility and Qt Webkit pre-installed.
• Starting from Symbian Belle devices have Qt part of device firmware
• Smart Installer will deploy Qt libraries when needed on supported S60 and Symbian devices where necessary libraries are not pre-installed (http://www.developer.nokia.com/Community/Wiki/Nokia_Smart_Installer_for_Symbian)

It should refer also to Nokia Developer site's Device database on more specific information what devices have Qt preinstalled and with which versions.
See: http://www.developer.nokia.com/Devices/Device_specifications/?filter1=qt

There's a reference to pre-compiled binaries to http://doc.qt.nokia.com/4.7-snapshot/install-symbian-installer.html. It refers to some file "qt-symbian-opensource-4.7.exe" but doesn't say where this can be obtained. In the Qt SDK the SIS files are directly available from Symbian SIS directory (at least on Mac). Perhaps this is completely outdated page and creates confusion.

The Symbian requirements page is also outdated or at least confusing for general Qt users (application developers):
http://doc.qt.nokia.com/4.7/requirements-symbian.html

It should mention that this documentation is if a developer wants to build the Symbian Qt itself. Merely using Qt for application development then Qt SDK can be used and the necessary Symbian toolchain will be installed together with it (on Windows) and on Linux and Mac Symbian Qt applications can be developed using Remote Compiler with Qt SDK.