I honestly can't say right now without completely pulling a prediction out of my ass or letting bias get in the way. There's simply too little data right now and too many factors that can affect the outcome of the sales.
But I will say this - Switch certainly has an excellent chance to sell more than Wii, considering how strongly it's performing in March/April, which is typically somewhat of a down time for gaming. It also has a high ceiling on account of being a handheld console as well, which means people will buy it for the conveinence factor, as well as having the potential to sell multiple devices to one household/consumer if there are redesigns, or just for the fact that people might each want to buy their own Switch. For these reasons alone, I think that Switch has a strong chance to outsell Wii. But the games - both quantity and quality, will be the ultimate determining factor. So far the console has a strong library and seems to be getting a steady stream of games just in year one, but will this keep up? Especially with very low western AAA third party support/confidence in the device? I think the library will almost certainly be stronger than the Wii U's, but who knows. All we have right now is speculation, and a very small sample size. Things are looking quite good though.
At the moment, I stand with my prediciton months back of 60-80 million sales for the device, but I certainly wouldn't be surprised if it exceeded that.
"We hold these truths to be self-evident - all men and women created by the, go-you know.. you know the thing!" - Joe Biden
