A. Gnome 3.0 is not going to be a nearly as significant of a change as GTK1 to GTK2 or from KDE3/QT3 to KDE4/QT4. It'll be a revamp of some UI features and depreciation of old features in a effort to remove dependencies and improve performance.
B.If QT is good and it is using C++ then what is the point to having two QTs? Why not just use KDE instead of Gnome? Why not just get rid of Gnome altogether if you think it should be all C++ or that it should be QT.. you already have everything you want, right?