The HD release of The Legend of Zelda: The Wind Waker has been a welcome boon for the Wii U.
Since the HD title was given a new lighting engine, updated 1080p graphics, and expanded gameplay features, sales of the Wii U in the UK surged by more than 685%. The Wii U has put any doubts about its viability aside for the moment. As to whether it's capable of competing with the Xbox One and the PS4 on the merits of new IPs and ports of titles fans want to play remains to be seen.
One strategy Nintendo could employ is giving any number of titles the Wind Waker treatment. Beautiful games were in no short supply during the Wii/N64 era. It's unfortunate that most of them (Wii titles specifically) lacked HD support from Nintendo. A lot of gorgeous games ended up looking splotchy and muddy on a higher end HD TV. The Wii could have certainly gone title for title with the 360 and the PS3 in terms of artistic and stylistic merit, but with no HD support their titles weren't as strong as they could have been.
These titles are primed for an HD remake from Nintendo and we would love to see them on the Wii U.