Everyman Chess's excellent Move by Move series seems to me to be a real boon to players of varying levels. While I can't imagine that a GM would pick up a book like The Scheveningen: Move by Move in hopes of learning a new opening system, a club player can do so with confidence.
When the series was first announced and the first book on the The Slav was announced I thought that the question and answer format might work out rather nicely. After all, I've always asked lots of questions of stronger players in my own efforts to improve.
I picked up the books on the Scheveningen, and on the English and enjoyed them.
However, when I picked up IM Cyrus Lakdawala's excellent book Capablanca: Move by Move I really saw what this series can mean to a player trying to improve. That book has improved my play more than any other book I have ever read. I found the book to be not only easy to read, but eye opening as well.
The explanations given are clear and articulate, and the variational analysis is not to overwhelming for a club player. In addition IM Lakdawala has a sense of humor that comes across very clearly and serves to add to the material rather than to detract (or even worse, distract) from it.
I am currently reading Kramnik: Move by Move also by IM Lakdawala and hope that player-specific books continue to be released.