The demos so far are in canvas, as I started learning Canvas recently. Thoughts on canvas:
-Very easy to share. Just load a page to view demo, and view source to read the code.
-Canvas is really slow.
2d vs 3d: After a certain level of scene complexity, I find it easier to do things in 3d rather than 2d, as you can just create the points and lots of things are taken care of for you. I don't think the web is a great platform for 3d graphics, and so I will be using Java applets and Open GL.
-A few more generated nature scenes etc like "Forest Night": beach,
-A stripped down format for drawing shapes in canvas
-A polygon, shape etc editor for canvas
-I don't know the word for this subject, but visualisations of entity interactions - eg predator prey, termites, game of life, boids, daisy world, iterated prisoner's dilemma etc
-Procedural city generation (from my existing C++ code)
-Terrain generation (eg mountains)
-Texture generation (eg I have seen algorithms that move pixels randomly in 3d, take a 2d slice and the texture looks something like marble)
-Plant generation (including 3d L-System turtles)