Coming from the Palm world, I have always used a tether strap and have never dropped a phone. It is handy for dragging out of the pocket and with living on a lake, it gives that extra sense of security when holding out over the water to take a photo. For my HTC EVO 4G, I attach the strap to the Otter Box case.
When you reach the age of 72, you will appreciate this also. The ElderTechTutor.
Darn, I was hoping to have an easy upgrade. I need wrist straps to keep from breaking my phone. Last phone I had without one died on the concrete sidewalk.
I dropped mine on our concrete driveway two nights ago from about 3 feet. It hit on the back and then flipped over on the screen and then slid (the driveway is slightly tilted) about three feet. The only damage was two small barely noticable scratches on the back.