Well... I believe you can buy a mic/headset, I'm not too sure about the attachment part. I know for a fact that you can use a headset on Resistance Fall Of Man, and some other games. Like I said, I'm not too sure about an attachment.
going off of what tbs said. It has already been stated that you can use a the same headset that you used for say socom. but nothing has been released about whether or not there is going to be a new one for the ps3.
Also, I'm not sure, but since the PS3 has bluetooth, can't you use a bluetooth headset as well. I have one for my music/phone. Would I be able to use it?