When it was first noted that JK Rowling would be publishing a novel aimed at an adult audience, I was quite upbeat about it; there was clearly an edgy side to the later HP books that I was excited to see develop.
The Casual Vacancy certainly targets the adult audience with hard-hitting subjects such as poverty and drug abuse, and strong characters with multi-layered personalities. There are a lot of characters, all going about different strands of the story which can sometimes result in a little bit of confusion (especially as some use nick-names as well as full names).
Unfortunately, the slow start and 'up-and-down' developments results in it being difficult to feel any empathy towards the characters until the last quarter-or-so of the storyline. Some characters have threads that are important to their development, but often feel dragged out which can take momentum away from the storyline in general. There are also moments where the subject - the local council - becomes just plain boring.
Sadly, there seems to be an unnecessary amount of swearing (even when you take the characters' personalities into account), which does make you think that there's a little bit of overkill in Rowling's attempt to prove herself as an adult author. I'm not being a prude, it's just that sometimes it altered my perceptions of characters in an unhelpful manner.
My rating is 3 stars, as it is a clever and thought-provoking story but not really executed in the best possible way.