So, we know that the game will allow us to go to a whole bunch of different locations throughout the solar system. Earth, the moon, Mars, and Venus are at least confirmed. (Did I miss any?) If we're planet hopping, I think it would be absolutely awesome to have different gravity effects depending on where we are in the solar system. Imagine jumping a few stories up on the moon, assuming we've got a pretty big standard jump on Earth. Just for reference, surface gravity on other planets relative to Earth's: Jupiter 2.543 Neptune 1.137 Saturn 1.065 Earth 1 Uranus 0.905 Venus 0.905 Mars 0.378 Mercury 0.377 Moon 0.165 Pluto 0.059