How much power can Nintendo fit into such a small semi-portable device? With the graphics on display I fear a return to the N64 era where Legend of Zelda ran at 20fps and Mario 64 ran at 30.
The N64 ran at low framerates due to its bottlenecked hardware. The Switch will be using a custom Tegra chip for its hardware, in other words probably the best thing they could put into something shaped like a tablet. It is "custom" after all so it can be on par with an X1 or more powerful than X2 we have no idea at this point.
Don't get your hopes up. This is all just advertising for the Switch. Remember the Zelda game they showed in the Wii U reveal? Completely different wasn't it?
The Zelda game shown in 2011 was just a tech demo for the Wii U's hardware and was never meant to be a game in the first place.