Ambassadors of FunkThe main music to World 1 was used in a single called Supermarioland and was released by Ambassadors of Funk Featuring MC Mario in 1992, which reached #8 in the UK Singles Chart.
LocationsThis is the only Mario game to include real world locations and enemies. Examples include fire breathing sphinxes, Chinese vampires, and the stone heads that appear in island nations. It is also the only Mario game that lets you pilot a submarine and airplane.
ManualThe manual for the U.S. version still lists all the enemies with their original Japanese names.
Information also contributed by STU2