Confirmed: Nintendo DS headset

Looks like an official Nintendo DS headset (not pictured right) is coming, albeit to Japan first. DS Fanboy writes: “Confirmed by the big N, this external microphone/earpiece (we’ll just call it a headset) will be releasing to the Japanese gaming public come September 14th for roughly $10 American. Rumor has it that the headset is going to be utilized by the upcoming Pokemon Diamond/Pearl, which will allow for full voice chat.”

What other uses for the headset could be beneficial?