Really? Qt used to be quite a bit snappier than GTK+. Is this no longer the case?

> OK, back to what most user will concern, the resource usage.

> To be honest, migrating to Qt will cause mild elevation of memory usage compared to the old Gtk+ 2 version. Don’t jump to the conclusion too soon. Migrating to gtk+ 3 also causes similar increase of resource usage.

http://blog.lxde.org/?p=1013

You are wrong.

1) QT works better when you not have accelerated drives (ie SVGA driver in X11)

2) The time in Nokia, QT was optimized to run in a mobile !! So must they tuned it to be more lightweight.