Oh sure, you could use the bluetooth headset that came for free with your phone. Better yet, you could use one you found online for $20.
However, those aren’t official. That’s what makes Sony’s so special… sort of.
The officially official bluetooth headset does have some benefits. For instance, you can see indicators on-screen (most likely when you hit the home button when in-game) that let you know the battery life left, signal strength, volume level, and whether or not you’re muted. The headset charges USB, and will run you about $45 in October – at least if you live in Japan. No word on when the US version will land, but Sony loves money so you have to figure it won’t take much longer after that.