well, since they are just a smidge thicker than the current 40GB regular iPod, i assume that you can use a 40GB case, but if i'm wrong, well, then i'm wrong.
I had had the same question when someone started another thread about the best iPod case. Apparently they offer two different sizes (A and B, I think--the website doesn't seem to be loading right now) and the website will tell you which size to order for your individual iPod model, including the two iPod photo models.