Nintendo is keen to get as many retail titles available as downloadable titles on both the 3DS and the Wii U. In regards to the Wii U specifically, Nintendo is:
…in discussions with the publishers by sharing with them our offer in this area. Through that process, if publishers accept it as reasonable, games in the digital format will be available from the launch time. There are no technical restrictions.
That “no technical restrictions” line makes me happy and, while it should have been that way for a while, it’s good to see Nintendo playing catch-up with such enthusiasm.