Above is a screenshot of a GTK Window Decorator running in the non-compositing mode of compiz.
This isn’t blingy though. So why is it significant? It means a significant amount of work is done on the GNOME side of things so we don’t need need to change window managers when you want to switch off compositing. It took a particularly long time to get right, simply because the original GTK-Window-Decorator wasn’t architectures with the fact that it might be painted to a window in mind, which meant that I had to rewrite the entire event handler, for example.
There are still a few bugs and I am in the process of fixing them.