I for one don't want to cancel my pre-order, nor do I want to advocate anyone else into doing so. I put down the money because I beleive in the people who are working on it will do a good job due to their past track records. I am excited for this book! I also appreciate the second sample that was posted and made me even more eager to get the book.
With that said, when people start to invest their money into something, in their mind it becomes less a labor of love that people are working on in their spare time, and more a real product. These people are now customers and investors, and not just community members. Anyone who has ever worked in any sort of customer service/customer facing field starts to understand how people interpret "the customer is always right".
I am not looking to disrespect anyone involved because I think the quality of the past efforts is going to be reflected in the current/future efforts (this book). I also understand that not everything goes as planned. It is like the quote I heard John Cash (id programmer) once say "I'd love to live in theory, everything works in theory". We are ALL excited for this, we just want the flow of updates to open a little more