OK maybe my last image wasn't clear enough.
how about this:
This is what a zoomed in image of a W looks like on an iPad 1 or 2, or an iPhone, 3G, or 3GS:
Image
Now this is what happens when we display the exact same image on the new iPad, an iPhone 4 or 4S:
Image
now if we remove the gridlines:
iPad 1 and 2, and iPhone, 3G and 3GS:
Image
new iPad, iPhone 4 and 4S:
Image
EXACTLY THE SAME!
the close up photos posted further up, i don't know about you but i think the Retina one is better, at normal viewing distance, what you call "jaggies" to me give a much sharper crisper image seeing as there is a smaller gap between the pixels, it's the other one that looks blurriest to me.
Wow I thought this thread was finished, we established that the same image displayed on a retina and non retina display will look different. I personally, and others, think it makes the old apps look worse when displayed on a retina screen. Others have said they make it looks better.
I appreciate the effort you went into to make your graphic, but all that shows is that the images are the same, we know that already as that is the whole point of the thread; the same image but on different displays.
the pixel pitch on the iPad 1 and 2 is 192µm, on the new iPad it is 96µm
so we are talking about pixels that are exactly half the size, spaced exactly half the distance away from each other, so where's the difference?
You said it yourself. The difference is the pixels are further apart on the old iPad, which makes the black lines (the gaps between the pixels) thicker. These thicker black lines create a "screen door" effect, and your brain fills in the missing information, creating a sort of antialiasing effect, make the jaggies less pronounced.