Like I said earlier, ASUS Transformer Prime. In regards to others comments on specs, ASUS Transformer destroys iPad2, and probably will be a tossup with the 3. But the ability to turn it totally into a laptop with the keyboard dock, even with the pad to control a mouse.... Transformer Prime is THE best tablet out right now, and almost certainly will be when the new iPad comes out.
But between Fire and iPad3? That's laughable if cost isn't a huge issue, iPad3. Hardware destroys the Fire + screen size.
you're right, the keyboard is totally the differentiating feature, if only people made one for the ipad
http://www.google.com/products/catalog?q=ipad+keyboard&um=1&ie=UTF-8&tbm=shop&cid=17683837378939772950&sa=X&ei=LRJUT_GNH-Xo0QGw04D1DQ&ved=0CI0BEPMCMAYas far as fire goes, it's half the price and the screen size works better as a reader (at least to me)