For as many books as Edward Longacre has authored, I don't think I've actually read any of them (maybe his Pickett bio years ago), but the subject matter of his new study Cavalry of the Heartland: The Mounted Forces of the Army of Tennessee (Westholme Publishing, 2009) alone marked it as a highly anticipated title for me.
Glancing through it, it looks to be a quite detailed operational history of the western cavalry [the main text runs almost 350 pages at a small print font]. The bibliography is extensive -- by my rough count, almost 400 manuscript collections were cited. There are ten maps altogether, two battlefield drawings (Ft. Donelson and Monroe's Crossroads) with the balance composed of maps tracing operational scale movements.
I think it's safe to say that western theater enthusiasts will want to grab a copy of this book, another good looking title from Westholme. From what I can tell online, it appears to be scheduled for general release in a week or so.