I would think that they didn't show it because it's not important to them: The controller and the experience is the selling point. As far as I'm concerned, they told us the three most important things, making "my penis is bigger than yours" type statements of hardware specs unneccesary.
1) It will output in full HD
2) It will have onboard storage (Based on John Riticello's comments that the system will be able to receive DLC and updates... I will try to dig up the exact quote)
3) It has an open online capability.
Honestly, over a year away from release, that's all I need to know that the big N is at least trying.
When I saw the new controller revealed I was excited by thinking about all the cool new ways games could be played using the touch screen and "hidden screen" for multiplayer. I was also thinking about how awkward it might be to hold something that big and how much it will cost to get some 4 Player Smash Bros. going. What's under the hood or how many dual-shaded polygons the system can push didn't even cross my mind for a second.