To Kill a Mockingbird is the UKs Favorite Book?

I just came across this article in The Guardian which begins:

Harper Lee's To Kill a Mockingbird has replaced previous favourites The Lord of the Rings and Pride and Prejudice as the nation's most-loved read.

Does anyone else find it odd that UK readers have replaced two VERY British favorites with a decidedly American story?

To Kill a Mockingbird is a great book (I have read it at least 3 times), but it always struck me as quintessentially American. I guess I need to rethink that opinion now.