Okay, I finally finished last night. This book took WAY longer to read than I'd expected. It was interesting enough, but kind of felt like a stretch, overall. I think the material would have done better as a long introduction to A Christmas Carol plus maybe a few nice long New Yorker or Atlantic essays - the history of Christmas in England; Dickens and the evolution of publishing; how Dickens's childhood informed his writing, etc. It felt like the author didn't really have enough material for the book he wanted to write, so he threw it all together and put references to A Christmas Carol on the front because he knew that would make it sell.
But it certainly wasn't bad, and if you're interested in this stuff, go ahead and read it. One thing I learned: several of the "Christmas books" don't actually mention Christmas. Hmph!
On to A Christmas Carol itself today!!