On the subject of handhelds coming to WiiU: I am pleased, but it isnt enough of a step in my opinion. I think this should have been announced and done right from the beginning. I think they should have also gone farther and made the WiiU be able to play 3DS games as well. Actual cartridge releases though. Like you could put the DS or 3DS game you already own directly into the system.
So far the WiiU still can't justify itself to me as a result. I don't want to be rebuying the DS (and hypothetically if it played them, 3DS) games to play on the WiiU. It would be nice if you could just type in the serial number on your game cart to get the VC download free though. I think if the WiiU did that I would go out and get one immediately.
You could even extend this concept into the really old games too. Not many people actually keep a game collection, especially after GameStop's trade in program started. They wouldn't be losing much off of it I believe, for the added functionality. I mean, they already log all of this stuff through your Nintendo Account, right? I would jump on the WiiU immediately if it did both DS and 3DS without me having to rebuy the games.
Hell, I would buy an additional 50$ add-on just to do this if they would release it. You know, like the GBA player. It would be worth it to me, and they could still do it now even after releasing the console without it first.