I have a thing for cases for my iPods. I'm not saying that they are easily scratched, but I tend to toss everything into my bag, so keys, iPods, wallet, assorted junk all end up sloshing against each other. Scratches happen. Additionally, iPods get dropped, and not always on a carpeted surface. This is why I love a good case. To me, a good case needs to cover more than just the back, if it's going to get tossed into the bottomless bag, or dropped on a hard floor.
When I got my first iPod touch 3 years ago, I settled on a Griffin flip case. There were cheaper cases, but the Griffin was well-made and offered the best protection. I've never regretted the purchase, and the case looks almost as good today as it did in 2007. When my 4th gen iPod touch arrive a few weeks back, I started the search for a comparable case for it. Locally, I've only found cases that cover just the back and edges, so last week I ended up back at the Griffin website. I don't like anything that involves a skin on the screen (can someone please tell my how to get those on without having any bubbles appear?), and I've given up on finding a good flip-up case, so I ended up ordering the ELan Passport metal. It opens to the side instead of the front flipping up over the top.
Griffin cases tend to cost more than others, but the quality of materials and construction makes it worth the little bit extra. I can't tell you how many times my original touch has hit the floor. I'm confident that the new case will protect the new touch equally well. The top button is recessed enough that I won't worry about something in my bag accidentally turning it on. At the same time, it's still easily accessed. The only thing missing is a cutout for the back camera lens. I'm not particularly happy about that, but it's easy enough to take it out of the case if I want to use the camera. At the same time, the sueded interior feels like it will keep it from sliding out by accident.
New case with the old case. (Decals added so I don't pick up my friend's case by accident.)
And yes, I'm still using the old one, too.