So: he's one of the current top Big Explainers, and The Signal and the Noise
Every single Big Explanation is wrong, with no exceptions, so this one is as well. Oh, it's pretty good, as Big Explanations go -- quite useful, in the right places, and a good tool for looking at a lot of situations in the actually existing world. But a book like this must insist that its Big Explanation covers everything in the world, and so Silver does, and so he's wrong, because nothing ever can do that. But his claim is elegant and not too obviously self-aggrandizing, so you can't stay grumpy at him for long.
If you know what Bayesian statistics are, you don't need to read The Signal and the Noise, only to know that Silver applies Bayes to baseball and politics, poker and weather forecasting, climate change and terrorism and the stock market -- all of which involve numbers and frequencies and lots of statistics, so they're fertile ground. If you only vaguely recognize Bayes -- if, like me, it's familiar while you read it, like the laws of thermodynamics and the carbon cycle, but slips out of mind immediately afterward -- then The Signal and the Noise will be pleasant and may make you feel quite smart. If you detest numbers and prediction, because the lord of the universe explained everything in this book you have right there, then you need to go sit in the corner while the grownups talk.
As long as no one takes Silver's Big Explanations absolutely seriously, it will be quite useful -- and thinking about probabilistic calculations in more situations would be a net positive for most of us. But I'm sure there will be a cult of Bayes -- like the Milton Freedmanites, I suppose, but more fond of brackets -- that insists that all of human life can and will be predicted. We always do have the stupid with us, though, so we can't blame Silver (more than mildly and half-heartedly) for that.
The Signal and the Noise has quite a lot of good thinking, some good tools, and an organizing principle that's vastly more correct than most similar books. For a non-fiction bestseller, this is about as good as it gets.