I've only had a quick skim through it, but it looks like there's some really nice stuff in there. Apart from the different approach of not presenting new classes, it reminds me a lot of my own Theorems & Thaumaturgy. Especially in the way the book's development is described in the introduction:
"This supplement started life on June 19, 2011 as a spell posted in the Workshop Thread on the Dragonsfoot Forums. The first spell posted was Lighten Load (not my best work, but I've included it from a sense of sentimentality). I would probably never have taken the next step, pulling together a compilation, if winemaker81 (Bryan) hadn't put the concept in front of me. In many ways, he deserves a lot, if not most, of the credit for this. I had no idea at that time that a single spell was going to lead to the crafting of over 150 spells."Compare that to what I wrote in my introduction:
"...the seeds of this project were planted several years ago, when I'd just started playing old-school D&D again, in the form of AD&D 2nd edition. I began writing some spells to fill out two of my favourite schools of magic: necromancy and dimensionalism. Shortly afterwards I discovered the unstoppable explosion of creativity that is the Old School Revival / Renaissance and began to share some of my creations. The positive feedback I received from the community inspired me to write more, and more, and more spells... and now here you are with this book."Definitely worth checking out!