Oddly enough, I almost never hit the right shift key. I touch type pretty fast, but the left pinky does a lot of work. I suppose it comes from CAD stuff and (let's be honest) WASD gaming where my left hand is on the keyboard and right hand is on the mouse.

But I totally agree: Input and output to the user (keyboard, trackpoint/mouse buttons/touchpad/screen) are of critical importance. I can be really effective on a decade-old Thinkpad (with the IPS display mod!) and woefully out-of-date processor, but if it takes too long to adjust to the keyboard I'll be frustrated every time I have to use it.