All iPads iPad Air is such a joke at $499

[rui no onna]

Someone stated earlier in this thread that Apple makes the greatest margin on the 16GB version. However, I would argue that, that Apple makes the least margin on the 16GB and larger margins on the 32GB and 64GB etc. The logic is that Apple charges a flat $100 for doubling storage. Apple's cost of doubling storage would be far below the $100 cost they charge. I would expect Apple makes the largest margins on 32GB and 64GB models.

Yep, margins are higher for the 32GB, 64GB and 128GB models. Assuming a fixed per GB cost, though, it's just the rate that those margins increase that goes down slightly with every doubling of storage. Did that math based on iSuppli's estimated cost and for the iPad 4 Wi-Fi, increase in profit margins is as follows:
16->32GB +9%
32->64GB +5%
64->128GB +1.5%.