Just watched a live demo of the same Qt app running, with a rather different form factors, on a Windows Mobile device and then on a desktop. A stated goal is now to unify development for desktop and mobile operating systems, just as Qt has already done this for desktop operating systems. Now they are talking about eliminating the differences between web 2.0 apps and desktop apps via WebKit and Qt.
More platforms, more continuity, less code to write. Qt 4.4 is going to be freaking sweet. As if 4.3 wasn't good enough already ;)
On a related note, Richard Hughes has put out a call for a Qt front end for PackageKit. Might make for a really cool project, no?