[citation][nom]rosen380[/nom]A 7.9" 4:3 screen is 6.32x4.74, 30 sq inches total
A 7.0" 16:9 screen is 5.94x3.71, 22 square inches[/citation]
Your numbers also reveal why Apple went with a 7.9" screen on the mini. It has nothing to do with 7" being a bad size. A movie shown on a 16:9 7" screen is just under 6 inches wide. A movie shown on a 4:3 7" iPad would've been 5.6" wide. By moving up to 7.9", they insured that a movie shown on an iPad mini would be bigger than when shown on a 7" Android tablet despite the aspect ratio being a worse fit.
In terms of comfort and portability, 7" is better. An A-sized paperback, which after a hundred years is the "optimal" size the publishing industry arrived at for one-handed holding, is 7.01" x 4.33". Add a bezel to the above tablet sizes and the 16:9 Android tablet is almost a spot-on match. The iPad mini is too broad.