The Host, by Stephenie Meyer

Bought this because I loved the Twilight books (trashy but fun to read) and I thought this was even better. It is not great literature, but was a really interesting story, very well paced - thought provoking and entertaining. Have lent it to a friend now and am looking forward to getting it back for a re-read.
It is a story about aliens using humans as 'hosts' but not at all science fiction, just a human love story really. Highly recommended.