The C-based GTK+ cross platform toolkit has now reached version 2.0. This version is the basis of Gnome 2.0 as well and its libraries are not compatible in either source or binary form with previous GTK+ applications. FAQ and release notes. The C++ bindings for GTK+ 2.0, called Gtkmm, is expected to be released very soon too. UPDATE: On a related note, Gnome 2 Beta 2 released for general testing.