It's no secret that all of these platforms and their games are readily available in emulated formats for computers and other devices. And it's easy enough to invest in a gamepad that's as generic as Nintendo's classic controller. For Virtual Console to succeed, it's got to be clean, easy, and cheap.
That said, the E3 Virtual Console demo featured an elegant interface (the downloading process was not shown) and superb emulation software. The demo featured a sampling of beloved launch titles, including Super Mario Bros. (NES), Super Mario World (SNES), Super Mario 64 (N64), Sonic the Hedgehog (Genesis), and Bonk's Adventure (TurboGrafx 16).
But there are still too many unanswered questions. A representative could not confirm if the interface featured in the demo would be the final version -- he suspected it was not. And there is still no official word about pricing. We do know that the classic controller will be sold separately, or perhaps packaged in with a special bundle. We don't know if Virtual Console games will be playable without the classic controller. And what about rumble support? Online multiplayer? Unique indie titles? The list goes on...
Sega Genesis 1st-gen
Nintendo SNES 1st-gen
NEC TurboGrafx 16
Nintendo Wii console