I hear eartones semi-regularly. So do many of the friends and family that I have talked to. But, even though some of us are in the same place when we are hearing a tone, we NEVER hear them at the same time. The strong ones certainly seem like a real phenomenon from outside my head, sometimes can almost make my ears pop...but that is just my brain telling me this, and perhaps it is easily fooled. I have never seen any link between eartones that I hear and earthquakes...but hey, I spend 80% of my time now in blue state suburbia...

It's interesting, but even with Petra's Parkfield prediction I ain't jumping on any bandwagons...
Chris