According to Nintendo of America President Reggie Fils-Aime, the company's upcoming Wii U will offer "a much more flexible system" for online gameplay where publishers and developers are free to choose the network solution they prefer.
"So instead of a situation where a publisher has their own network and wants that to be the predominant platform, and having arguments with platform holders, we're going to welcome that," he told Forbes. "We're going to welcome that from the best and the brightest of the third party publishers."
This means that it would be possible for Wii U players to play with their PC counterparts if the game developer wishes so. Valve is already eyeing Wii U to host some of its upcoming titles, and if this happens it is likely that they would use their Steam platform for multiplayer.
Reggie refused to elaborate on the subject, saying that it would be better if further details were "to come from the publishers than to come from us."