Although personally, I would want and actually even much prefer more extensive and intensive introductions and supplemental cultural/folkloric details, since truly and certainly, the bare-bones information which John Langstaff has provided in his The Season for Singing: American Christmas Songs & Carols just seems to and even a bit frustratingly, temptingly whet my folkloristic appetite only to leave me hungering for more (and indeed, suggestions for further reading, for further research and study would also have been much appreciated), Langstaff's compiled selection of specifically U.S. American Christmas songs and carols is most certainly eclectic and thankfully also contains a goodly number of offerings not all that universally and standardly known (and yes, each featured song choice is also presented with both lyrics and musical scores, as well as the necessary guitar chords, a required and even assumed given for a songbook perhaps, but still very much and gladly both appreciated and cherished).
And for me, because I am not all that aware of and well versed with and in the traditions of American Spiritual and Gospel based Christmas song fare, my personal favourite section of The Season for Singing: American Christmas Songs & Carols, at least at present, is and remains the chapter which presents and features primarily the former, but really, all of the five sections are in many ways pure musical delight, and I also do hope to soon start practicing on my keyboard and my recorder so that come this December, I will perhaps be able to play a varied smorgasbord of these carols (for some different musical Christmas interludes than the more standard German, French and English language songs and carols with which I am most familiar). Highly recommended, but seemingly not in current print, although The Season for Singing: American Christmas Songs & Carols is still and nevertheless quite easily and readily available second-hand (however, it must be stated that if you are in fact looking for a more traditional book of Christmas carols that primarily presents and offers such standards as Silent Night, Oh Christmas Tree and North American Santa Claus types of songs, you should probably consider looking elsewhere).
The specific American focus makes this a little less useful as a stand-alone songbook for Christmas, as Americans themselves have never limited themselves to home-grown songs and carols and gatherings will surely demand traditional European ones in addition.