We released some extra C++ bindings recently:
libnotifymm and hildon-notifymm
Johannes Schmid created libnotifymm (svn, tarball) to wrap libnotify, and we also wrapped Maemo’s hildon-notify, though there’s no documentation to say what this does beyond regular libnotify. I suspect that Maemo should just use a port of libnotify without requiring use of special API.
There are lots of examples in the libnotifymm source code. It seems quite simple, and particularly useful for code that uses Gtk::StatusIcon.