I'm getting a lot of emails already, so from now on I will officially accept pre-orders for the new FLEX book.

Pre-ordering is absolutely non-binding. If you send a pre-order email it just means that I will put your name on a list and send you an email when I have more info about pricing etc.
There's nothing to pay yet, and if you don't want a book in the end, just don't reply to my announcement email.

the email for preorders is preorder1@flexpunk.com

I don't have any pricing information yet, there are just too many unknown factors (especially the number of pages), and I haven't even started to look for a printer.