We have and 13 and 15" rMBP in the house ... I find the keyboard on the 15" a lot nicer, better tactile feel, more 'springy', better feedback, its hard to describe. Hate to say the 13" keyboard feels cheaper or less responsive but it does, my wife's 15" rMBP feels smoother and faster to type on, been comparing them yesterday and today, thought it was just me, but had others try it this evening and they agree. I wonder why, less room to work with maybe or I'm wondering if I just got a bad one? Seems unlikely but I haven't been able to get to an Apple store to try any others. Anyone else tried typing on both the 13 and 15" rMBP?