I have a iPhone 4 on att. While I'm talking on the phone if I receive text notification it plays the notification sound loudly in my earpiece. It might be just me, but I honestly don't remember this happening before upgrading to ios 5.
I have played around with the settings but figured I'd hit the forums to see if anyone else has noticed this. Like I said just might be me but figured I'd ask. Hope everybody had a good weekend!
It's always done this ever since I got my 3GS on ios3. Never changed. Vibrates in your ear as well. I hate that. You would think apple would have that fixed. I Like the text tone playing but not the vibrating thing.