Its pretty good...
No seriously, believe all the 10 out of 10 reviews you see. Its an amazing game. I binged about 12-13 hours playing it this weekend and all I want to do is play it some more. The open world they have created is just spectacular (and massive). You literally can go anywhere and I found myself just exploring things for hours. It runs pretty well even on my Wii U, only when there is a lot going on the screen does the frame rate dip a bit. The combat is pretty fun and you can attack each situation differently. The enemy AI is really good and certain enemies won't just blindly charge you. They will actually dodge your incoming fire and come at your from different angles. The game can be really challenging at times.
I only have a few nitpicks, but they are pretty minor. The story line gently guides you, but the game is very non-linear. Which sometimes can be annoying, as I occasionally wandered into enemies that were way too powerful for my present weapons or ability. Sometimes its hard to determine if you can take on a bad guy or not. Most of the time its learning out the hard way. You will die a lot.
Another is that your weapons and shields have a limited life. Some are far more durable than others, but many lower powered items break really quickly. Its not uncommon to use up multiple weapons on a single tough boss. I don't mind the mechanic, but I feel like at least the weapons are a bit too fragile. Also, you always seem to be short on arrows. Stockpile them when you can, as the bow is one of your best weapons.
The game also doesn't explain things very well at times. Like I didn't know you can surf on your shield until multiple hours into it. Also, that you can register your horse at a stable so that you can grab it at any stable in the game. But those examples are few. A lot of the fun in the game is discovering new things.
I don't think I'm going to bother getting a Switch for now, as some of the reviews are so-so. However, if you are on the fence and don't have a Wii U, the Switch might be worth it for this game alone.