With today's announcement I think it would be interesting to look at the screen sizes and resolutions of the various generations of iPod's that had color screens.
Today's release was now the 4th gen Nano following up the two generations of Mini in similar sizing.
1st Gen - 1.5" - 176 x 132 pixel - .168-mm dot pitch
2nd Gen - 1.5" - 176 x 132 pixel - .168-mm dot pitch
3rd Gen - 2" - 320-by-240-pixel - 204 pixels per inch
4th Gen - 2" - 320-by-240-pixel - 204 pixels per inch
It seems like they are using the exact same screen on the 4th gen and have just rotated it 90 degrees to shrink the overall package.
Also today came the second release of the Touch.
1st Gen - 3.5" - 480-by-320-pixel - 163 pixels per inch
2nd Gen - 3.5" - 480-by-320-pixel - 163 pixels per inch
No changes there it seems.
The classic has gone through many revisions, however I am only going to talk about those that had color screens.
Color - 2" - 220-by-176-pixel - 0.18-mm dot pitch
Photo - 2" - 220-by-176-pixel - 0.18-mm dot pitch
5th Gen - 2.5" - 320 x 240 pixel - .156-mm dot pitch
5th Gen V2 - 2.5" - 320 x 240 pixel - .156-mm dot pitch
Classic - 2.5" - 320-by-240-pixel - 163 pixels per inch
Classic 2nd Gen - 2.5" - 320-by-240-pixel - 163 pixels per inch
Again it seems like same old screen that has been there since the original 5th Gen. I think the latest ones are more power efficient and probably better at video.
One interesting note is the pixel density is the same on Touch and Classic just different size screens but the Nano has much denser pixels.
Wow, I didn't realise the classic and nano both had 320x240 screens... i've got a nano and my mates got a classic and i guess the size of the classic makes the screen look bigger.