Ryan Cash noticed that the white iPhone 4 is slightly thicker than its black counterpart. In the image above you can see that the white plastic is slightly thicker. Apple lists the depth of both devices as 0.37 inch (9.3 mm).
I wonder if this will affect the fit of existing cases. I’ve noticed that the DODOcase BOOKback, as thin as it is, prevents my black iPhone 4 from fitting inside a Mophie Juicepack Plus. If you can test a white iPhone with an iPhone 4 case, please let me know (especially if you’ve got a micrometer or a vernier caliper lying around).