I've read four or five Anita Shreve books, and I feel that this one belongs lower down the heap. The problems are that from the beginning you know that things are going to 'come to a climax' and with that in mind there are only a couple of ways it can go, making it a bit predictable.
Telling two stories in parallel, with the story from the past filtered through a character in the present, is a nice structure, and one Shreve has used successfully in the past.
On the upside, the setting is very interesting, the Isles of Shoals. I've always had a thing about islands, something that I go on about a bit on my blog...
She makes the bleak, bare islands with their peculiar names practically become characters in the story.
As for the actual characters in the story, they're unsympathetic across the board, which though i didn't mind it too much, it might be a problem for other readers. The lead character is a photographer, and because of this the book is constantly focussed on detailed visual descriptions of characters and scenes, which are often poetic and sometimes quite beautiful, but there's just, quite a lot of them...
So, if you like very visual books, with unsparing character examinations, intense, morally vague and fairly clipped, this is for you...