Spore's going to be massive.
To be honest, I hadn't really paid that much attention to Will Wright's terminally delayed simulation-of-everything over the last few years. For one, I'm not exactly into sim games, whether of the big-S or small-s variety. Another, the concept just seemed so impossible: Going from a cell to a creature to a civilization to space? Yeah, good luck finishing that.
Rather than force the player to start at the "cell" level, you can instead select between any of the five different parts of the game right from the start. While this is certainly sure to be a controversial decision -- it takes a lot away from the sense of growth and expansion that I believed the game would have if it forced you to start from the beginning -- it'll let anybody jump in wherever they feel most comfortable.