Well, I can offer some other opinions. I was at the 3-5 PM slot.
What I played:
Project P-100
I NEED THIS GAME. NOW. This was easily the best game on the floor, no questions! When described in a nutshell as "Viewtiful Joe + Pikmin", I feel it's accurate. (With an awesomeness multiplier) The gestures prime your hero's unite attack, and then you can go to town combo-ing with it. (I tended to prefer the sword, but my friend loved the fist. The gun was pretty cool too, but a little unwieldy.) Left trigger lets you jello-mold defend, and with good timing I could get the enemy robot to stagger himself by bouncing off of it, and then combo like crazy. Right trigger lets you dodge, by having everyone in your group jump to the side in a large arc. There's also a normal "swarm" attack with X, which was a good way to build up some damage before usng hero moves. There's a battery and life system that I didn't quite figure out, but you needed battery power to use your hero moves. Otherwise it's standard run with the stick and jump with a button. (You can double jump and explore around to find more batteries and things.) You can also lift cars and things and chuck them at enemies, as well use the Hero Fist to lift BIG things, as well as turn large wheels. There was a portion in the demo when you went inside of a garage, and then you had to view the Game Pad screen to check out what was inside. Seems simple enough, a little gimmick but still cool. I also loved conscripting civilians and random other former heroes by drawing a circle around them with the Pad. (I can't draw circles apparently, so it took a few tries.) You get graded after each act, (Time, Damage taken, Combo) and I managed to get a few golds. Definitely an amazing experience, and one that bizarre-and-awesome-GAF would love.
ZombiU
Okay, I suck at FPS games. Kind of a fact. Additionally, the guy running the screen didn't really tell me what all the buttons did. Still, this is pretty intense. Ran around beating up some zombies with a cricket bat before realizing that by dawdling, I had drawn a swarm of six around me. When you get grabbed, you do have what amounts to an "extra life" by ramming an emergency syringe into the zombie's neck. Kills that one, but doesn't do anything about the others. Using the right trigger, you can shove, and by holding the left trigger to "Ready the weapon", you can use the right trigger to attack. Using the crossbow via the Pad was pretty cool, I do love the Silent-Scope-esque detail I got. Also cool was the "Scan" system, where if you hold the left shoulder, you can use the Pad as a sort of AR scanner ala Metroid Prime. It shows a grey, sort of static-y screen, and any bright spots you can hold an "analyze" button on the touch screen to let you know if any containers or zombies are carrying anything useful. There is a bit of a radar on the pad as well, and the "rummaging" pan out is very effective. The other detail I think is pretty cool is that I believe there's only one of each weapon in the game world. So if you've found the shotgun, (and it is GOOD) but your survivor carrying the shotgun gets bitten, you're going to WANT to hunt down your former-survivor-now-shotgun-hoarding-zombie, because damned if you're going to go around shooting things with the pea-shooter your pistol is.
New Super Mario Bros U
A nice, solid platformer. Played the first level in a competition, (speed run) and won a hat. The "create-a-platform" feature is pretty nice, as well as the ability to knock back or otherwise stun enemies. (Though my Pad-using teammate managed to push a goomba back so that my jump landed right in front of it and I bodyslammed it, shrinking. >_> Sheesh.) The Squirrel Suit is pretty fun to use, and I like the fact that we've got a nice glider. (Didn't get to mess with it very much.) If one likes 2D Mario, it looks like it'll be satisfying. I do hope for trickier levels earlier on, but we'll see how it goes.
Rayman Legends
On the other hand, this was definitely higher in difficulty. Murray (or whatever the Pad Fairy is named) is a great device. He cuts ropes, nails enemies, gets more...point thingies, and really forces a teamwork aspect with the platforming player. Apparently in single-player, you control both Murray and Rayman. Got to use the Wii U Controller Pro. VERY comfortable, and the stick/buttons difference didn't cause me any trouble in the slightest. The gameplay of kicking and punching is still there, and the rhythm-y rock out running level was AWESOME. This is another one to definitely look out for.
(I...didn't really get to play Pikmin 3. Disappointing!)
Nintendoland
Only got to play the Luigi's Mansion pseudo-Pac-man-Vs. game, but that was fun. I have to admit, Nintendoland looks far less fun than it actually is. Get a few friends together, and this is a ton of fun. Chasing down the ghost requires a lot of verbal communication of "Ghost is in my Zone, I'm Luigi!" and without teamwork, you just get owned by the ghost player. I think Nintendoland really comes down to a "gotta try it and see if it's to your taste", because it's a lot of fun, but it's not a "deep" experience if that's what you're looking for. Fun, simple party games suggests to me that as a pack-in, it'll do fine. (The instructions are pretty simple. Normal wiimotes can use one button to "sidestep" and another to "shine light", and the idea is to shine the ghost to death. As you shine, the beams get shorter. Get batteries to recharge your flashlight, revive scared allies with light, and don't split up too much or the ghost can sneak behind you and pick you off with its dash move. The wiimote vibrates when the ghost is near, hence the need to communicate. Still good fun.)
Game And Wario
This feels kind of tech-demo-y as well, but the games are still fun to play. I'm a little disappointed it'll only be 10 games. I played the Jimmy T. skiing game. Simple enough to play, and I got to enjoy Jimmy T being the fabulous dude he is. Don't mess with the blue 'fro! Gameplay consisted of turning the Game Pad on its side and using the gyro to maneuver him, and shaking the Pad to do tricks during jumps. Nothing complicated, but quick fun is still good.
ZombiU Multiplayer
Let's just go with Left 4 Dead, but you get to be the director. Capture the flag, careful placement of running zombies and others can make it VERY difficult for the survivors indeed. This is quite the blast to play, and I can see a lot of time being put into it.
I did not check out Sing, Just Dance 4, Wii Fit U, Ninja Gaiden 3, or Batman: Arkham City. They did NOT have Tank Tank Tank or Scribblenauts on the floor during my timeslot. (Which sucks, because those are both pretty fun according to the staff.)
Wii Fit U looks like it's pretty good at tricking you into exercising. Gamification at its finest, I suppose. Not really my thing, but I think it'll do okay.
I've come away from the Experience thinking "Well, I need to get a Wii U so I can get P-100. And play P-100. I wish I could play more P-100. Man, I sure am thinking a lot about P-100."
So yeah, similarly, ask any questions if you want, and I really would love another chance to get my hands on it. According to my girlfriend, Pikmin 3 added a dodge-roll, which allows for faster action and makes the game SO MUCH BETTER! Rock Pikmin are nifty, and the game is an excellent addition to the Pikmin family.
Edit: also, the Wii U Game Pad is REALLY light and comfortable. I'm surprised as it looks far clunkier than it is.
Additionally: They had a photo section where you could pose with plush rupees or a yoshi or 1-up mushroom. Didn't take advantage of it, but that was kind of cool.
They also had some free snack-y stuff. Bottles of Wii-U Experience water, Blue Lemonade (berry flavored), Blue cotton candy, fruit kebabs, blue-frosted glazed doughnuts, and mario-themed cake pops. I think my tongue is still blue.
Also a shout out to blurrygil for working the event. Good seeing you again!