With the release of GNOME 2.22 we finally made an API/ABI stable release of glibmm with the new giomm API. We went way past the GNOME API freeze date, which was scary and unwise, so there are sure to be some undiscovered problems. But we are quite sure that any remaining problems would be things that we could fix by deprecation+addition.
There are some giomm examples in the gtkmm-documentation module and the giomm API reference is not too bad. For instance, see Gio::File. Hopefully I will find the time to write a chapter on giomm for the gtkmm book.
Thanks again to Marko Anastasov who did all the initial wrapping work and to Jonathan Jongsma and José Alburquerque. Jonathan Jongsma is now officially a co-maintainer of glibmm. I’ve pesuaded him to do tarball releases after glibmm 2.16.0. Now I must persuade Marko to become a co-maintainer of something.