I got interested in this book because I really enjoyed the film Gosford Park, for which Julian Fellowes wrote the screenplay. It took me a while to get through it, even though it isn't that long, simply because I had a bad feeling about where it was going. I don't like to see people make fools of themselves or get hurt.
It's fairly amusing in its skewering of the still-extant social castes in modern England, but the story focuses on the ascension of Edith Lavery to the haughty Broughton clan and the not-so-hilarious hijinks that ensue. Which is not to say that it's a total downer, but it does have its rough bits.
Overall a fair bit of light reading, but nothing that I would gush about and then recommend to everyone within earshot.