Looks like the screen size is 5.66 inches.

Above that - running at 1000MHz core clock (and apparently using just 10W) it's rated at 512GFLOPS...keeping in mind that it's nVIdia and their GPUs FLOP for FLOP usually perform somewhat better than AMD counterparts.

It also has 16 TMUs and 16ROPs, which at 1GHz have much better texture and pixel fillrate than WiiU.

So in other words, it's more powerful than Wii U?

Probably in most areas except memory bandwidth. 

Actually, X1 has 25.6GB/s memory bandwidth, plus it's Maxwell, so it has same compression as current desktop parts.

Wii U has the eDRAM though at 32MB that's above 100GB/sec I believe. 

Though Nintendo already uses eDRAM on the 3DS (10MB in New 3DS though only at 30-50GB/sec apparently). 

Still if Nintendo can get a good chunk of fast eDRAM on their next handheld and AMD can give them a GPU on par or better than the X1 ... Wii U ports would be doable for sure. 

Ninty should just have nvidia make their next gen consoles, if they could run those games that'd be the 3rd party support they need. Hopefully they can make an ARM home console much more powerful than that shield console thing.

Given their track record, Nintendo having GPU on par with Tegra X1 for their next handheld would be nothing short of...I think unbelievable is the word I'm looking for. But everything's possible I guess.

Depends on what they want. 

Honestly the next-cycle PowerVR Apple iPhone/iPad GPUs could possibly outpace the X1. 

Not bad at all. Was kinda interested in the original Shield Portable mainly for the sake of streaming PC games. Hoping they improved the design though, the original looked a bit too bulky & uncomfortable. As long as the price isn't too high I can see myself getting one.