So the summer of code has reached its hands-down phasis and few minutes before the deadline finally height-for-width support has landed:
Proper support for rotated labels with ellipses also has been backported to GTK+:
Well, but end of Summer of Code doesn't mean end of hacking: Have to teach GtkHBox and GtkTable the size-for-allocation trick. The icon view could profit from exposing such information. Well, and finally the extended layout branch has to be merged into GTK+ trunk, which currently is feature frozen.
Guess this Summer of Code was quite some success for me: Implemented some useful features and finally managed to fully join the GNOME community.