Heya GAF, I've been thinking this through, and comparing the WiiU's reveal compared to the Wii, and I've come up with this:
This years E3 was much alike the first announcement of the Wii - if you remember, no games were shown during the Wii's first reveal, just people's reactions and a sneak peek at the system and stuff.
Later on, the controller was revealed, and a few more details.
The Wii U got a little more than this - game demos shown etc. - but much like the Wii, I believe the biggest dump of info will be at next years E3.
Many people thought it would be fully announced with games this year and released the next, but I think Nintendo are going to push release to the middle of next year, after E3.
This way they can show a ton of third party and first party games (which was notably lacking from this year's conference). In much the same way that the Wii changed design in that year gap, I think Nintendo will alter the WiiU somehow.
There's been a lot of attention and controversy over the controller and it's apparent single use per system. With enough feedback and commentary, I really wouldn't find it surprising if Nintendo re-thought there launch plan, and maybe altered the concept of the controller a little to enable multiple use of controllers on one system.
I know to many this may seem incredibly unlikely (with an arguably short amount of time left, nothing drastic will change), but I reckon release is further away than you think. Hell, some of Ninendo's own divisions have only just got dev kits.
All in all, I reckon this is the prototype phase for Nintendo.
The GPU may be tweaked, controller assessed and multiplayer capabilities finalised, all between now and launch.
I for one see a repeat of the Wii launch situation, and we're kinda at stage one at the moment.