Unfortunately does nothing to change my view that authors should probably keep away from their own reviews. If he'd had some brilliant new insight that would be one thing, but instead he just comes off as slightly more defensive than anyone who has sold tens of millions of books should. I guess it was 1999 when this was written, though, so the norms for online reviews had not yet been established.
It's one thing to fake a review, but there's nothing wrong with using that spot to talk to your readers.