Earlier this year, guessing the iPad mini's weight based on weight/volume of other devices.
What might the next iPad 5 weigh?
The current iPad mini is 0.93 oz/in³.
Assuming the iPad 5 was the same height of 9.5", but was narrower with about the same on the sides as the iPad mini for a width of 6.5". And thinner, the same as the iPad mini at 0.28".
Using the same weight/volume number: That ends up with a weight of just about exactly 1 pound = (16 oz = 453 grams).
To compare, the current iPad 3/4 is 1.44 pounds, and the still selling iPad 2 is 1.33 pounds (and the iPad mini is 0.68 pounds), so that's considerably lighter even if I'm off by a few percent. Nice.