Rumour is better cameras, laminated screen, thinner body, Touch ID and 2 gigs of ram. Should be a fantastic update. I've been waiting for a laminated screen on iPads since iPad 1.
I guess LCD-glass lamination would also bring back som of that "hard tactile feel" which I reckon the first-gen iPad had much more of than the later models, with their still-thinner cover glass.
Not that the "screen drumming" on iPad Air is necessarily bad I guess, I really found the "granite feel" of the first-gen glass satisfying though, especially for typing. Somewhat a preference thing obviously. Might feel more like that again now if it's been made into one solid mass.