There are a few things that, when taken together suggest to me that we'll see a machine that at best will hit parity with XBO/PS4.

1) Nintendo have already stated they think the Wii U was too costly to purchase and Nintendo's own history suggests they like the US$250 price point

2) Nintendo need to remain profitable after struggling to get back there this last couple of years

3) Nintendo don't really care about specs per se. So long as the machine does what they need it to do.

4) Nintendo have been building partnerships, primarily with Japanese developers. They know their Western third party ship has well and truly sailed.

5) They have, and will continue to branch out with their IPs into other areas like toys, theme parks etc

So in 2016 they should be able to match a 2013 console's power at a reasonably cost.

I haven't bought a Wii U but my expectations are high for this one, hopefully it meets them!