Shinnok's proposal was chosen for development. See Johnny - GUI for John the Ripper for more details.
These are JtR GUI proposals for GSoC 2011, by different authors:
Johnny is a GUI concept to John the Ripper written in C++ using the Qt framework.
John the Ripper Working GUI
John the Ripper new GUI
John the Ripper GUI
Advanced GUI concept
Such amount of buttons is bad. Some buttons (like open, close, append) could be moved into menus while some groups (like file joining and splitting) may be done as dialogs that will occur when necessary.
Simple GUI in Python (v0.01)
Sources and binaries at the same time: external link http://code.google.com/p/aleksey/files/john_simple_gui.001.py
Simple GUI in C++ (v0.01)
Sources: Stored on this wiki, external link http://aleksey.googlecode.com/files/john_simple_gui.001.cpp