> You find 9-10" is insufficient for reading material?
No, I find 12 - 13" better for reading material. The reason my Retina iPad became my default "book" is because it was sufficient. :-)12.5" is the 'printable' area of an 8.5 x 11" page with 1" margins. (14" if you include the margins). So especially for PDFs that are 'zoomed to the margins' a retina 12.5" display can be pretty much a 1 for 1 reproduction. And that is something I've wanted for a very very long time.