GNU Octave 3.8 was officially released on 31 December 2013 to close out the year. As covered in my original article, Octave 3.8 has its own graphical user-interface and uses OpenGL in conjunction with FLTK widgets. There's also new functions in Octave 3.8, new regular expressions, and a ton of other work to try to better position Octave as a competitor to MATLAB.
The new GUI isn't being made the default until Octave 4.0 as there's still more work to take place, but overall it appears in good shape for the 3.8 milestone.
More details on GNU Octave 3.8 can be found via the official release announcement at GNU.org and the 3.8 NEWS file.