Prior art does exist already for the page flipping
I worked for HP Research Labs in Bristol from 2001-2002 on a project for e-book readers. Before I even joined the project they'd worked out that page flipping would be a good idea. We developed a prototype where you used a touch strip on the edge of page, moving towards the centre for normal page turns, then on the same side of the page, moving towards the edge to 'riffle' the pages. So intuitive in fact that we only wrote it up as a white paper (they had one patent already up their sleeves). So, move along, keeping walking, nothing innovative to see here, move along there.
Of course it could be an inside job (discruntled HP employee fired post Compaq merger), gone native at Microsoft.