Nintendo has the official spelling with a a lowercase "m", to fit with the Game Boy micro's small size.
The Game Boy micro is Nintendo's smallest handheld to date, measuring 2 inches high by 4 inches across, and only .7 inches deep.
By holding the L button, you can adjust the screen brightness through 5 different settings using the volume adjustment switch.
This small handheld even includes a standard 3.5mm headphone jack, something the Game Boy Advance SP did not.
In North America, the standard Game Boy micro units (Black and Silver) did not include extra faceplates. However, they did release two different bundles that included 2 additional faceplates. The Black bundle units received silver, camouflage, and flame faceplates. The Silver bundle would give you black, ladybug, and ammonite faceplates.