I didn’t get around to blogging about gtkmm 3.8 when I released it last month, partly because we had to fix a crasher bug and do a gtkmm .1 release before people noticed.
Anyway, just a little while after GNOME 3.8 was released, we managed to release gtkmm 3.8 and glibmm 2.36. There is quite a bit of work in these, almost all by José Alburquerque and Kjell Ahlstedt, as well as the usual few days of last-minute work by me to wrap remaining new API.
I spend very little time on glibmm and gtkmm these days, and don’t have much motivation to change that.
There’s also a change that we expect in glib 2.38 that will break many installed applications that use gtkmm. We successfully begged the glib developers to add a special case for us in glib 2.36, but we have not found any way to avoid this for 2.38. So far our best option seems to be to do a new parallel-installed gtkmm (and glibmm) ABI, leaving the old (broken with glib 2.38) one behind, at least allowing applications to be changed slightly and then rebuilt.
Personally, I have no great incentive to go through that pain.