Times
What most people - OK, most men - have failed to notice about romantic fiction is that it has suddenly become very funny.
A current survey of the most successful romantic fiction writers reveals a band of jokers: Helen Fielding, Lisa Jewell, and the former stand-up comedian Jenny Colgan.
If you want laughs from a book, turn to these women rather than to the male farces that rely on tired gags about infidelity - see David Baddiel, Nick Hornby et al.
Much of the credit for this welcome revolution must go to Marian Keyes, who was one of the first romantic novelists to have the confidence to send up the ridiculousness of love.
Readers responded with a passion, and her four previous novels have been bestsellers for the past decade.
In future, feminist historians may also note that she is unique in making two further departures from the conventional romance.
First, in Sushi for Beginners, as in her other books, she devotes much of her attention - and humour - to the details of office life.
Lisa Edwards, a pretentious fashion magazine editor who is imported from London to Dublin to launch a new magazine, is a workaholic, though in Keyes's world this is no sin.
In fact, the doomed character in the book is Clodagh, the pretty girl who married young and had children, but who has no job and therefore no self-respect.
Ashling, Lisa's deputy, is the most sympathetic figure, vying with her boss for the attentions of Jack, a publishing executive.
But what the three women have in common is that they are all on the brink of a nervous breakdown, triggered by suppressing problems they had when they were growing up.
And this is the second of Keyes's great innovations: the mixing of romance with serious and often uncomfortable issues.
In Rachel's Holiday the love interest formed a small part of what was actually a very funny account of alcoholism: in Last Chance Saloon, life-threatening cancer triggered the jokes.
Keyes does not balk at leaving her heroines single, and neither is she afraid to let her comedy run very dark indeed - in fact, this is her sustaining talent.
So Sushi for Beginners does disappoint in that the first half is spent in relatively frothy form. Only when the going starts to get tough for the three leading women do the jokes begin to pick up. The loneliness and self-doubt of the proud Lisa are excellently written, but the other characters often seem to be sketchily drawn.
Keyes has also taken the brave step of setting the book in Dublin, rather than London and New York as usual, which will do wonders for the Irish capital's fashionable profile.
However, the book is still readable and funny and its sales will no doubt affirm her place as reigning queen of romantic fiction.
But Keyes's reputation is such that the standard expected of her is more exacting and this is not a book that surpasses her others. Perhaps she just wanted to give male humorists a fighting chance for a change.