Harry Potter author J.K. Rowling's first adult novel went on sale amid a buzz of anticipation Thursday -- but reviews suggest those hoping for a repeat of the charms and wizardry of the Hogwarts books may be disappointed.

"The Casual Vacancy" is firmly aimed at those in the grown-up world, with the writer's pen dissecting social inequality, small-town politics and snobbery -- with sex, abuse and a mouthful of swearing thrown in for good measure.

Set in the fictional town of Pagford, in western England, it centers on a local election following the death of a parish councilman -- and relies on what reviewers agree is a cast of finely drawn but generally unpleasant characters to bring this insular world to life.

"We are firmly in Muggle-land -- about as far from the enchanted world of Harry Potter as we can get," wrote Michiko Kakutani in The New York Times.

"There is no magic in this book -- in terms of wizarding or in terms of narrative sorcery. Instead, this novel for adults is filled with a variety of people like Harry's aunt and uncle, Petunia and Vernon Dursley: self-absorbed, small-minded, snobbish and judgmental folks, whose stories neither engage nor transport us."

The Guardian newspaper's Theo Tait judges it "a solid, traditional and determinedly unadventurous English novel" but praises Rowling's depiction of the "claustrophobic horror" of a small-town community, with plenty of scheming and "everyone knowing everyone."

Sales of the book, which was released in paper, online and e-book form in Britain and the United States on Thursday morning, will no doubt be closely watched.

But while Rowling's publisher, Little Brown, and booksellers seem confident the tome will prove a bestseller, the mad rush and predawn lines that awaited some of the Potter releases were not in evidence.

Early sales seemed slow at a central London branch of the Waterstone's bookstore chain, where stacks of the hardback novel, with its stridently red and yellow cover, were unwrapped and ready for buyers.

Waterstone's spokeswoman Debs Tilley said preorders had been "fantastic," suggesting Rowling commands a legion of devoted readers willing to give her new venture a try, even if they're not beating down the doors to the store.

"Having known and loved her writing for the past 15 years, the world has been waiting to see what she did next," Tilley said. " 'The Casual Vacancy' has reminded us all just how popular she is and how committed her fans are."

Store manager Lori Fazio of R.J. Julia Booksellers in Madison, Connecticut, told CNN that interest in the novel had been building for months, with lots of advance orders. "People can't wait for this, for it to finally hit the bookstore," she said.

While the book is certainly different from Rowling's previous works, Fazio predicts it will win fans if readers realize it's "an extreme opposite from Harry Potter" and go into it with an open mind.

Harry Potter is certainly a tough act to follow. The seven-book series sold more than 450 million copies and spawned a multibillion-dollar film franchise.

Details of the new book's content were kept largely under wraps ahead of its release, with Rowling speaking to only a few media outlets in the United Kingdom and the United States. Those critics lucky enough to get their hands on an advance copy also had to keep their reviews on hold until Thursday.

But one young woman in London told CNN why she's looking forward to reading it. "I think it will be really interesting to see how J.K. Rowling writes something else that isn't Harry Potter, that isn't aimed at children or young people," she said.

"I've heard lots about 'The Casual Vacancy' as being a political satire and more of that, so it's going to be nice to see if she pulls it off."

A representative for Little Brown said that presales of the novel had gone very well and that the idea behind the limited prepublication access to the book was to make it as "normal" a launch as possible.

The first print run in the United States is 2 million copies, the publisher said.

But with limited information leaked beforehand, many parents will probably be wondering Thursday if the book will appeal to -- or perhaps be suitable for -- children who have grown up loving Harry Potter's world of muggles and magic.