There's just one review of the Mason book at Amazon, and we got 2 out of 5 stars.
Pretty painful. I think most of the reviewer's comments are off-base. The first criticism is that the book is aimed at people who already know mod_perl and Mason. I can't speak to the latter, since I can't read the book as someone who doesn't know Mason, but I can say there is not much particularly mod_perl specific code that couldn't be done almost identically with CGI.pm, and there just isn't that much mod_perl stuff in general. I don't think you need to know Mason already to find the book useful. At least, it goes through everything the docs that come with Mason cover, in more detail. If the existing docs were sufficient for Mason's current (large) user base, I'd assume that the book can only be an improvement for new users.
The review also says that the book doesn't have enough practical examples until chapter 8. I think there's some truth to this, and we do say in the preface that readers may want to read chapter 8 after the intro. OTOH, I'm not sure that we could have put a lot of "practical" examples in the earlier chapters, since many practical examples require you to understand more than just the basics. But that doesn't mean the examples couldn't be better, and some of them may be too contrived. I think many books which aim to introduce a topic suffer from this problem, and I'm not sure that it's actually solvable.
I do think it's funny that the reviewer called those earlier chapters "academic" and "theoretical". I'm not sure how learning the basics needed to build real appliations could be considered academic or theoretical.
Yet another complaint is that in Chapter 8 the example site uses Alzabo for all the database bits. The reviewer thought that this module is "not very well known". True, but the only well-known module for talking to a database is DBI, and there's no way in hell I was going to stick raw DBI and SQL into the components. Mason is about presentation, not logic. Combining the two is just bad design, and most of chapter 9 talks about exactly this concern. Plus jamming all the logic in the the components would make them even bigger than they already are.
In other words, logic belongs in modules. So even if I didn't use Alzabo, I'd just have to write custom modules to wrap the SQL, and any custom modules would have an even less well-known API. That would hardly be an improvement.
Finally, the reviewer says there aren't enough graphics or screenshots. There are certainly very few. I'm not a very visual person (I prefer reading text) so that may explain why I only thought of one place to put a graphic in the chapters I wrote. I can't speak for Ken. Suggestions for additional graphics in future editions would of course be welcome, but I can't think of any places crying out for a graphic in the current edition.
Anyway, I just had to get this off my chest, because I think these criticisms are at least partially bogus.
If anyone reading this _liked_ the book, I'd be thrilled if you'd post a review. If you didn't like it, you can post one too, of course