Last year I abandon the book for various reasons. It was painful, I like to finish what I started. I made a quick announcement on my website and I just stopped publishing any more news, it was painful to even think about it.
But the book is back. I started working on it again. I actually finished the bulk of the writing and it's now in proof-reading stage. I'm happy with the state it's in and I would publish it as it is now, but proof reading is making it so much better. This means that I believe it's a high certainty that this book will be out and out soon.