I wasn't familiar with Trine 2, so the fact that Trine 2: Director's Cut was heading to the Wii U didn't really mean much to me. But when I saw the game on the monitor, I was sucked in by its beauty. Yes, I am that superficial.
But seriously, this game is beautiful. Trine 2: Director's Cut is a 2D platformer/puzzler, and everything from the characters to the backgrounds is full of HD detail. This is one of those games you can play independently on the GamePad as well, and I swear it almost looked better on that than the monitor (perhaps the color wasn't calibrated just perfectly on the TV).
You play as one of three characters: a female ranger, a mage, and a warrior, and work your way through level after level by defeating enemies and solving puzzles. You have to cycle through the characters to find the right one to advance, but the game design is such that there are sometimes multiple solutions to each problem. (Which is helpful when say, your mage is dead, and you need to solve a puzzle to get to the next room where you can resurrect him.) The controls are a little bit complicated, but you'd probably get used to them eventually. Being a demo, I often got confused as to what button I should be pushing. Also, and I know it's only a minor irritation, really, but you can't cycle L and R to move through the characters. Only R. So you have to go around again if you miss. Luckily, there's only three characters! Oh, and you don't really use the touchscreen on the GamePad too much except when using the mage, where your touch activates his telekinesis, or a swipe creates a platform you can use to bridge gaps (if they're not too long).
Since this is the Director's Cut, there are a lot of extras. It includes the Goblin Menace expansion, which includes the Wii U exclusive level "Dwarven Caverns," as well as new powers and abilities. There's also an extra two-player co-op mode called Magic Mayhem, but that's all they would tell me about it at the time!
Trine 2: Director's Cut is looking extremely polished, and with all the multiplayer and hidden items and abilities to collect and upgrade, it should prove a solid addition to the Wii U library when it releases (sometime during the launch window).