It's amazing how someone can draw conclusions about an entire industry from the amount of errors in a single book, and it's corresponding errata page.
IF book publishing is dying, then that is simply due to a decline in the demand of books, something which I suspect is not subsequently due to typos, but more likely, something a little closer to do with our ever changing interests.
In the case of tech books, I think it has more to do with ever changing technologies. And if that's the case, then we need a new breed of tech books that can evolve with technologies, be updated in parallel with the technology it covers. And the tech publishing industry doesn't seem to be ready to evolve in that direction. It's Manning we're talking about. And look at the time it took to O'Reilly to release a half-decent iPad app for Safari Books Online. And even now they are limiting the number of offline books to 3! I mean, don't they know that we tend to use books as references more than we read them linearly.
And this is not the first book I encounter this kind of issues with. It's just the first one where it's so annoying that I can't help posting about it. And behind these books, there's a process, there's a way of doing things, talking about pages and online erratas, that's so outdated that yes, if they don't evolve, they're gonna die.