Your thread title and the question posed in the body of your post are quite different. In answer to your title: I have faith in Wii U sales because they have continued to increase YoY - I'm one of the few who think it will actually do even better next year. In reply to yourpost itself: what exactly do you mean by comeback? Do I think it's going to beat out the Xbox One and Ps4 in units? No. Do I think it's going to match GCN sales? Maybe. Do I think it's going to turn a profit? Definitely! Do I think Nintendo will end up makeing more money this gen than Microsoft (Xbox Division)? Yes. Sony? Maybe.
I hope that answers your question. It should end up being a "success" in that it will make money for Nintendo and facilitate another console/more games in the future. I have faith in that.
Retro Tech Select - My Youtube channel. Covers throwback consumer electronics with a focus on "vid'ya games."
Latest Video: Top 12: Best Games on the N64 - Special Features, Episode 7