Good book, especially if you're new to the whole HTML5 thing or need to read up on certain API's. This is a book by Klaus Förster and Bernd Öggl from 2011 (recent!). Unfortunately the marvellous cover artwork was not repeated in the book, I liked it. I guess I've seen too many animals there ;)
I generally liked the book. The structure in the text makes it easy to read away and even my wife told me that she liked the markup and said that if she would be into tech, she'd probably liked to have read this book. For whatever that's worth to ya ;) The book also has a website with all the examples and way more.
I do have to note that from time to time, the book goes too far off in examples. Especially CSS pointers (for insofar irrelevant to html5) were a bit annoying at times. Also quite some time was spent on examples of entire pieces of code (like one or two games), without really showing any example of the API. I'd have preferred some API reference and some short practical examples related to them.
Another point of critique is using a lot of "at the time of writing, this and that browser do support it but none of the others do". While these sort of remarks are dangerous on a blog post because they'll be outdated and are unlikely to be fixed, they certainly won't be fixed in paper book form. And while I suppose I could appreciate such information, at times I felt like there was a little too much focus on certain browsers supporting it. The book is about the API and I would expect it to sport theoretical demonstrations of the API where practical examples are lacking.
I haven't seen many mistakes. Actually, I just remember finding one very small minor typo. That was nice because I usually spot several errors in these kind of books.
The book covers the transition to html5, the new tags and the new API's. It shows you the range of new form tools to your disposal. Of course the video and audio API's are covered, as well as canvas. SVG and MathML are briefly touched on. Geolocation (even though that's "not really part of HTML5"). The several storage API's are discussed as well, followed by some web socket love. Web workers are also demonstrated. The book closes with a full chapter about microdata and some of the global attributes introduced by HTML5.
However, the spec is much much bigger than the points that were touched on. Sure, the important parts have been covered, but I feel it could have gone much deeper. Both on the semantic aspect of the spec as the features and API's (like the File API, for instance).
If you're into paper books and think some of the HTML5 API's are not that clear to you, I'd recommend this book. It's a good read and has a nice layout. If you prefer to get your information from
the web, this book is probably not for you. It won't offer you anything you can't also get online.
Publisher's website for this book