Note: This section is rather incomplete. Don't be too disappointed if you can't find the information you need and please come back when this Wiki is officially opened.
Todo:: Would it be useful to have information about the GUIs and development tools in a fixed format to make them more easily comparable (see WebProgrammingTemplate and WebProgrammingTemplateHelp). Some categories: directly supported widgets, addon widgets, layout managers, ...
Some available GUI's for Python:
Anyone for a GuiProgrammingShootout?