Interestigly enough, the book gets good reviews on amazon.co.uk and bad ones on amazon.com.
I go with the UK. I'd read her previous novel, and I do not really remember what I thought of it - but I am sure it was not as good as 'Divorcee'. 'Divorcee' is a good laugh, and very, very light.
Do not expect rounded characters or deep analysis or even - heaven forbid - a realistic depiction of New York City. The people live on a different planet, where clothes are their life and where they can fly off to Mexico, St Petersburg or Spain for the weekend. Total escapism!
So what? The writing is light-hearted, there are many bon mots, and not much is demanded of the reader. Just what is needed when sunning oneself by the swimming pool on vacation in January. Go for it, enjoy.