The new Qt SDK 1.1.4
brings major stability, performance, and functionality improvements for the much improved Nokia N9 Harmattan target as well as the Qt 4.7.4
"bundle" for all Symbian^3, Symbian Anna, and Symbian Belle smartphones. You now have better tools than even before as well as a large installed base of modern Symbian phones and the Nokia N9 to target with Qt apps.
For Qt on Symbian, the release offers closer integration of Qt into the Symbian operating system services. Qt graphics system, split view keyboard, and support for Symbian Belle UI features are all included. In particular the improvements with regard to the Qt Quick Components 1.1 and Qt Quick 1.1 modules are significant – and will truly ease and speed up development. The Qt 4.7.4 release bundle for Symbian contains Qt Quick 1.1, Qt Mobility 1.2, Qt WebKit 2.1, and Qt Quick Components 1.1.
With regard to the Nokia N9, the Qt SDK Harmattan target is now a full release and installed by default. Other visible changes are the evolution to a single unified sysroot (no tools-level distinction between Platform API and its more productised subset), a single target (with debug and release flavours of the build), and major up-dates to the documentation.
Read more here
@ Qt blogs.