Allison Pearson can, as we already know, write. Her forte is wonderful observations, pithily put. The resonance of what she writes about (I have two children; my wife and I both work) made me laugh and cry several times.
You should read the book if the above sounds good to you. If you want to read a story, however, be warned. The story doesn't start until page 288. Before that, you'll be embroiled in the hectic life of Kate Reddy, forever wondering if the plot possibilities she tees up will ever come to pass. Once you get to page 288, when Kate Reddy is confronted by events that require her to start making choices, you'll find major events dealt with very sketchily or barely mentioned in passing; the author skims over the few elements of real story that exist in the book. At times, it seems the author 'chokes' when faced with exploring how her heroine might develop when not merely coping with working motherhood.
I like a good storyline in novels. Maybe Ms Pearson was just too busy to put one in.