I'm the project manager of Crystal Space and recently I started a new OSS project based on Crystal Space called AresEd. This is a 3D game creation kit. You make assets like models and levels and blender and then import them in AresEd. With AresEd you can then create the actual game by putting objects in levels and assigning game logic to them in a graphical manner.
Here is my reply that seems relevant to a larger audiance than just the old blog discussion there:
Personally I don't think "graphical" programming will ever get of the ground... it is just too limiting and once you have to deal with a mix of logic bricks and python code (see BGE) you have just added another set of complexity to it and not actually simplified the game programming at all (compared to just using python).
The best way IMHO is a well separated scripting environment (with an relatively easy script language) so that a user doesn't have to deal (or get confused) by the engine internals. Add to that an extensive set of well documented and self-contained game-play script, so that you hardly ever have to write something completely from scratch, but rather are able get something nice running by simply cut&pasting stuff quickly.
And while commercial game engines have realized that more or less, there is basically no FOSS engine that does it like that.
Any further thoughts?