If you watched the 2005 GDC video, it had a lot of gameplay. Of course, there's not much to show right now since there's only a few dozen (or hundred at best) creatures. Remember, in the first video, Wil Wright said that the start of the game is more like a "tutorial" for the space stage. You could concievably play any game you want - Galatic Civ, or Galatic Zoo.
Personally, I'm gonna see if I can create a planet by smashing asteroids together, and plopping down a few amoeba, and play with those. (Maybe even make the planet a really huge desert planet, or ice planet)
To sum it up:
GDC 2005 - Wil touched on all the stages of the game. He tried to touch on the tribal and stages a bit more - he's the SimCity guru, of course!
GDC 2006/E3 2006 - After much fan discussion on what they wanted Wil to show (animal stage - mostly the creature editor, and space stage), that's what he focused on.
During GDC 2005, he didn't show a whole lot of options, probably for two reasons - 1, he had a limited amount of time to speak, and 2 - many options probably weren't finished (just placeholders) or buggy.