Hell no WiiU won't end up in second unless it really takes off with Amiibo in a completely unpredictable insane Pokemon-esque way.
However, it will remain in second place for perhaps another 12 months from today.
WiiU has pretty much sealed its fate to final sales of 16-25 million.
Xbone is much more uncertain, but also has much more potential. 25-65 million.
MS could maybe even exceed my expectations if they take on the risk. However I also think there's that slight chance they see little profit and seeing ground lost from last gen say "Screw it!" and don't fully support the product, instead focusing elsewhere. I think that's a small chance though.