Rating: 

What I liked about the book were the document examples in the beginning. The %coreattrs, %events and %i18n attributes should be easier to find (they are not listed in the TOC). I think, required attributes should be listed before optional ones.

What is missing (as some readers also remarked in the errata list):

- color names

- some words about other character tables

- some words about http-equiv

- ... and about the use of other attributes like <area>-coordinates. A sentence like "The syntax depends on the form" is poor.

But still, as I don't know a better book of this kind, I do not regret having bought it. It's handy and useful, in spite of the errors. But maybe O'Reilly should think about withdrawing it and reworking it before damaging their reputation.