Here are some more details for Super Mario Galaxy, courtesy of gamefront:

• Mario has the jump attack we’ve seen, but he also has another variant on this attack that we haven’t seen
• If you press the 1 or 2 key in the demo, the game asks if you want to return to the map in the observatory.
• Once again, the gravity varied on different planets, allowing for higher or lower jumps
• There is one planet in the game that is 10 times larger than the average planets

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