A caution must be issued right up front about this book: this is not a book of lore or ritual/personal techniques. If that is what you are after, this book will not fit your needs. A Modern Celt--Seeking the Ancestors (Mabh Savage) is a "fire-side chat" book; it is a rather informal collection of the author's experiences, tales from her family, and accounts from her friends about experiences gained by coming into contact with the lore and deities of the Ancient Celtic people.
For those people who have experienced the fire-side chat mode, that time after a ritual or lesson when you are sitting around a bonfire (or in the case of lodge members--during the after-ritual dinner) talking to your teacher and fellow students and seekers, the style of this book will be familiar. It is a rather informal book, one that my professors in college and university would have imploded upon reading. It is a step above gossip, generally on the level of the stories that one tells when one's coven (study group or lodge) has became a familial unit of sorts.
This style may be strange to those who have been practicing and studying by themselves, or who have gotten involved in the "strict lodge" setting where students are forced to hang out only with others of their particular grade and degree of knowledge. Hint: the fire-side chat mode is the start of the oral traditions that one hears about.
This book is not heavy on knowledge or techniques. It is a retelling of personal stories. And it will be a comfort for those who have experienced similar events, and educational for those with open minds who have not. I think that the book is worthwhile reading, despite the lack of spoon-fed lore and techniques; but I imagine that there will be readers who take issue with the book because of the lack of information and detail in it (one cannot say that I did not try to warn them off).
Is the information that is given accurate? This is a hard question to answer, at least for me; I am not an expert in Celtic paganism. But I do have a benchmark to attempt to hazard a guess, and that is how the author treats the Celtic Tree Calendar. For those who do not know, the Celtic Tree Calendar was created almost completely out of thin air by Robert Graves during the "paganism has survived underground, and my wild theories is what the ancient pagans actually thought" mode of the pagan revival (the Golden Dawn of the 1880s and the Wiccan books of Gerald Gardner are other examples of that particular stage of the pagan revival). Basically, there is no evidence to indicate that the Ancient Celts used such a fixed calendar, not alone the one that Robert Graves expounded upon.
There are three modes of dealing with the Celtic Calendar: 1) insisting on the truth of it...mainly because one loves the idea that paganism survived underground clear up to the start of the pagan revival; 2) completely abandoning it...because only actual Celtic practices should be used; and 3) splitting the difference...acknowledging the fact that Graves made the Celtic Tree Calendar up, yet using the result because it serves a purpose.
Mabh Savage belongs to the splitting the difference camp. She acknowledges the fictional nature of the Celtic Tree Calendar, and then proceeds to gather some actual tree and plant lore from the Ancient Celts to illustrate that Graves was not pulling it completely out of thin air and that there might be a grain of usefulness in the Celtic Tree Calendar. As someone who belongs to a group that does much the same with the Celtic Tree Calendar, I like that approach (the group that I belong to uses the Celtic Tree Calendar because it needed a Celtic knowledge system that could be represented in diagram form...it is a lodge thing).
Overall, given the fact that book is meant to be, essentially a set of fire-side style stories about how modern Celts are interacting with the deities and practices of the Ancient Celts, I give it five out of five stars. (It would suffer a loss of at least one star if one decided to judge it based on lore or techniques--something that the book is not really about.)
[Disclosure: This review is based on a pre-publication version provided by the publisher.]