I see something similar to the original design posted in this thread.
Touch screen controllers, a compact system, wireless controllers, mini disc sized media.
The design above would have 4 wireless controller ports, with a tiny display above the controllers telling you which frequency each is being broadcast for each controller, wether the system is loading, online etc.
The controlller itself would have a touch screen in the middle with a GBAsp sized screen (pixel wise)and a small number of pixels on the bottom would tell you how much power is left in the controller, below that a built in microphone. Now regardless of what nintendo says, the controller will still have a couple of traditional buttons so I've placed an A and a B button on the right side but they could just as well put start and select or whatever. On the left side I have a Dpad and an analog stick, at the bottom of each controller handle there'd be a spot to put a DS style thumb strab depending on where you'd want it for the game you happen to be playing, for purely stylus based games you could take another strap that'd be included and fasten your hand onto the controller so the other hand would be free to use the stylus without putting the controller on a surface.
The dock I drew would be for charging the controller, if worse came to worse you could use the controller while it charged up but much like a GBA it'd slow the process considerably. I'd forsee a battery that could be charged at any time so you could leave the controller on the dock and it'd fill itself up .
Other things of note- Memory cards would again be used , there would be 3 slots on the back of the console , one for memory cards, one for DS games and a 3rd one for GBA titles.
Things that would likely make the cut- Rumbling controllers might go the way of the do do, moters would drain battery life to quickly in the wireless gamepads, online play- though the controllers would be able to wifi link up with a DS for picto chat only , the console itself I really can't see having any sort of online support. Nintendo just doesn't think they can make money off of it, and given that the gamecube modems were underused pieces of junk I can't see them even wasting RD time on a modem for Revolution... until such a time when they feel they'd use it themselves.
Finally- the media format- the same size as a gamecube disc physically but data storage 10 times that of a cube disc. Using the blue laser light to get more stuff off the disc, there'd be different levels of data storage to max out the potential as well. So there'd be a dvd layer filled with audio files and such, and a blue laser layer filled with data and videos.
I think that about covers my idea, I'd expect all these innovational technoligies to limit 3rd party use of this thing once again, it'd be to costly for anyone but the largest companies to port games to revolution and use all its gimmicky features, so I'd expect muchlike the cube and N64 before it, a barren nintendo only console. sure you'll get EA games , possibly activision and ubisoft , coupled with the odd exclusive japanese game but don't expect to buy this thing and be able to play the best 3rd party stuff from Xenon and ps3 ... it'll be home to lots of exclusive content.
ADDED- I just noticed a flaw that I'm hoping nintendo doesn't do themselves, with a touch screen controller- the idea Ihave has the screen in the center like a DS but it'd make more sence for the controller to have the screen along only one side of the system, in fact I should just redraw the controller- picture one of those ascii 1 handed RPG gamepad for playstation, but with a screen on the right side of it and a smaller grip underneat to hold the controller, the buttons I mentioned would fit right beside the screen and wouldn't be used so much.