[NOTE: I'm not going to get into the substance of the story; I know folks who are reading the book and don't want to inadvertently spoil any of it for them. The review at Crooked Timber, which pointed me to the book in the first place (review linked below as well) will give you the basics.]
This book, Jonathan Strange and Mr. Norrell, by Susanna Clarke, is long. Too long. Despite what other reviewers have to say about Ms. Clarke's mannerly prose, she needs an editor.
She also needs a story. The last 200 pages actually had a story developing — coming to a rather quick end at the end of the book — but the first 600 pages that set the thing up were woefully boring and almost pointless.
I realize that she was likely going for an old-time mannerly feel in her writing, but she needed more story to pull it off. The footnotes with faked history and background info were helpful in this respect, but the main body was just too boring, at least for me. I would've been much happier with this story if I'd only had to read 400 pages to get to the end.
Next I'm reading The Reformation: A History by Diarmaid MacCulloch. 800 pages on the history of the Reformation — now that's a story!