Definitely getting one. I'd like to make it a little thicker to make it easier/more secure to hold and to give it a little drop protection. Also hoping a case will make it so that the camera lens doesn't stick out.
I can't stand using my iPhone in a case. Especially the Bumper. But I do want to protect it when it's in my pocket for extended periods. So I got a Sena Ultraslim and love it. More of a pouch / slipcase but it's really thin. And leather.
I ended up picking up a Speck Candyshell. A little pricey, but it provides great protection (it covers most of the bottom, unlike most cases) and the thickness makes the touch feel just right in the hand.
I picked up a Logix TPU case with screen protector at London Drugs for 15 dollars. It makes it easier to hold and looks really nice too. Smokey colour on a black iPod 5.
I have small children that are on my phone all the time so I need a case. I got the Otterbox Defender case. Seems to protect my phone completely from my children and there clumsy hands.