Just finished reading this book. It is very good, full of useful guidance on teaching to read, which is based on sound ABA principles. Although my daughter is not hyperlexic, a lot of the techniques shown will be applicable to her.
Another great find which I wanted to share with other parents of children with communication delays:
http://www.amazon.com/Teach-Language-Aspergers-developmental-disorders/dp/0965756505/ref=cm_cr_pr_product_top#_From what I have seen in the available preview, this book makes a case that it IS developmentally appropriate to teach reading early to such kids, as they are quite often strong visual learners and assimilate information much better if it is presented to them visually rather than orally. Shame this book is so expensive to buy!