Only a couple years after the launch of the Wii many analysts speculated that Nintendo would release an updated "Wii HD." While this proved unfounded, many of the core ideas behind this (an HD system that could play Wii games) ended up in the final product.
Meanwhile, Nintendo began seriously planning the sucessor for the Wii in 2008. The idea of the second screen on the GamePad arose from the idea that gaming consoles are dependent on televisions while televisions can fulfill many roles without consoles, which may compete with the console for the television's use. The second screen was meant to provide constant and detailed information about the console itself, something that could not be captured by the single blue light on the Wii. This evolved into Off-TV play and the use of the GamePad as a Heads-Up Display in games.
The Wii MotionPlus add-on and Wii Remote Plus controller for the original Wii was also released during this period, along with compatible games such as Wii Sports Resort. The Plus controller was seen as an ideal controller for what it was, and a good option for multiplayer. Wii control options would thus be compatible with the Wii U and incorporated into a number of games.
In April 2011 a leak revealed that the Wii U, at the time codenamed Project Cafe, would be announced at E3 2011, and would be a full HD system. Leaks about the controller from sites like IGN claimed it would be similar to the Nintendo Gamecube controller, but these proved unfounded as well, as they missed the controller's primary feature, its large touchscreen.
Later, 01Net leaked genuine details about the controller, correctly identifying the 6.1" touchscreen, front facing camera, sensor bar, and general mechanics of the design. CVG and IGN later chimed in with reports about the controller letting players stream games to it.
