I hope that rumour is true. If it is, I'll be there in the morning on Day 1, to grab an iPad Mini with Retina screen.
Right at this moment, I'm reading a Polish book using 2 iPads: iPad 3 and iPad 1 -- the original language on iPad 3, and a Slovak translation of the same book on iPad 1 as a secondary screen, in case I can't figure out something in the original language. However, 10 inches for a secondary screen at which I only look occasionally, is unnecessarily large, and two full-sized iPads are rather unwieldy to handle. iPad mini would be perfect for me as a secondary screen!