hello,
today i see the first packages with version number 3.12, among them are:
libgtk-3-0
libgail-3-0
gir1.2-gtk-3.0
libcheese7
libcheese-gtk23
and cheese-common, which replaces: cheese (<< 2.30.1-1)
Dist-upgrade still didn't want to remove any gnome packages.
But be careful and read what your apt is going to do with your very own individual package list!
The transition will hit us soon!
greetings
musca