Throwing in my two cents as one of the few people on the planet who hasn't read the HP series. (My kids were the perfect age as the books came out: young enough to love them, old enough to read for themselves.) I pre-ordered THE CASUAL VACANCY and inhaled it the minute it hit my Kindle mainly (I will admit) because it's a remarkable moment of publishing history, but I was quickly drawn into the story. The characters are people I already know, because they are the people we all already know. In the end, I liked this book on its own merits. And I liked it a lot.
Rowling is a terrifically strong writer; you can't fault her on craft, and I like that she doesn't feel the need to do any acrobatics or post a billboard - THIS WAY TO THE BRILLIANT WRITER - on every page, as is the irritating case in a lot of literary fiction. If you're able to set aside the JK ROWLING of it all, you'll love or hate this book on the strength of what it says about people. Folks. Relationships that are the opposite of magic. Politics that are petty. The youthful compulsion to crusade - at any age - and the crusty compulsion to squash the crusading of others.
Early on, it's noted that Samantha "enjoyed [Miles'] pomposity with precisely the same spirit as she liked, on formal occasions, to wear a hat," and Rowling is able to enjoy the faults of these characters the same way. These are the characters Franzen would write if he had more tenderness and less literary dyspepsia. Observations about resonant, everyday dynamics - conversational currency, backhanded charity, the lie of self-sacrifice - are made with more wry than sly and not a whiff of self-righteousness.
This is a quiet book; some will say cozy, but I think there's enough edge to prevent that. I loved the dry Britcom humor. A thousand little understated zingers make THE CASUAL VACANCY a pleasure to read in the way that the Mapp and Lucia books are a pleasure. You can definitely see Rowling's love for Jane Austen...if Jane Austen had known how to shoot up heroin. As life unravels for the people of Pagford, we have a goldfish bowl view, but that understated tone keeps things from going totally soapy.
A book that kept coming back to me as I read was Joseph Heller's SOMETHING HAPPENED. I can't think of another instance where an author from whom so much was expected took on the profoundly risky task of reminding us that there is nothing more human than the mundane.