Like everything else in the world, a degree of it is subjective. The things I most appreciate is that it requires less typing (and no use of things like class generators and other things) to do the same things using GObject/etc. I also appreciate the QPainter API, the fact that everything is wrappered in a nice, fairly consistent manner, and API which isn't cross-platform is clearly marked as such (e.g. QMaemo5 classes).