From Jenny’s post:
To participate, just read one of her books and post a review during that week! I will be collecting links and writing my own reviews and remarks about her every day that week (failing some sort of alarming computer failure, which (knock wood) I don’t anticipate). If you haven’t read anything by Diana Wynne Jones before, I will be only too happy to recommend a good book to start your Diana Wynne Jones fandom. There are many to choose from.