must say that the texture for the click wheel looks too pixelated compared to the screen. maybe look into anti-aliasing your click wheel texture or something... also check to make sure you've got the same font that apple uses to ensure that you've got an accurate texture.

one other small gripe is: lower your render resolution. you have your ipod centered in a rather large render, when the whole model takes up somewhere around a third at best of your entire render. either render smaller and zoom in, or shrink your image down in photoshop after rendering. (the former would be preferred, as most people don't want to see lots of background, just lots of the model you're showing off)