I wavered a bit. I may have given this one three or three and a half stars, but this was mainly due to the fact that the book is a bit on the thin side compared to some of the other Saga offerings, which strikes me as odd given the subject matter. That having been said, I think there is probably more per page that will be useful, so long as you are dealing with Force users in your campaign, than in some of the other sources.
Not only are there some really interesting powers (and well incorporated ones for some tricky EU powers), but the Force Regimens, basically training that you can undergo to give yourself a boost to some other aspect of your character or to give yourself a sort of Force psuedo power, if you have the time to practice, is great.
There are rules for Force spirits, training padawans, using different types of crystals in your lightsaber, and a bunch of new Force Traditions. Some of these have appeared before, but its kind of nice having them consolidated in a book about the Force, all in one place.
There are several new Dark Side related beasts, templates for Sith Abominations, NPC statblocks for Dark Side villains that, while used for iconic characters, could be modified pretty easily for an individual campaign's dark side villains.
Probably the most negative thing I could say about this book is that I'm not sure I need stats for Luke when he's 20th level, or other good Jedi characters, but I have to admit that in a way, its interesting to see the RP translation of characters that I've been reading or watching for years.
Overall, a pretty good buy. I just think I would have forked over the extra five buck for a larger tome, but maybe that's just me.