As stated, Saunders is a brilliant writer. My first encounter with him was with Tenth of December, which is his forte: short stories. I can still recall several of those heartbreaking tales (think: Raymond Carver) tempered by currency (think: Kate Atkinson, sorta). And, it's certainly true that this novel could be thought of as a series of extremely short stories. It's really more of a discussion, or a series of extremely short letters.
I was certainly put off by the structure, and I would forewarn readers to be aware of this. It doesn't take too long to figure out what Saunders is managing to create, and the more comfortable you get with it, the more it reveals itself to you. At its center, this is a novel about loss and regret - in and of itself nothing new. But it isn't just the structure that makes this something different. He is also taking a true tale (you'll see real quotes from real people in certain chapters) and refactoring it to his themes.
I would never call Saunders' work pleasant to read, because he delves into murky, uncomfortable, squishy personal areas. But I would say that I took a powerful lesson from this book, and actually found it a valuable read for the beginning of the year, in the vein of New Year's Resolutions.