Jessica Seinfeld, however, has done no such thing.
For starters, the timeline is all wrong. Cookbooks take a year or more to produce. Lapine's book came out in April, and Seinfeld's came out in October. (Disclosure: Seinfeld's book was published by HarperCollins, which is also my publisher. However, I have no relationship with anybody involved in the Seinfeld project, and I write my own books.) There was simply not enough time to incorporate Lapine's work into Seinfeld's. In fact, Seinfeld's agent told CBS that her book was already being bound when Lapine's came out.
Much has been made of the fact that Lapine originally showed her book proposal to HarperCollins and that HarperCollins rejected it, only to sign up Seinfeld soon after. To those unfamiliar with the world of book publishing, this may seem meaningful, but it's very unlikely that anybody at HarperCollins would have leaked the Lapine proposal to the Seinfeld team, particularly since the premise of the Lapine book is not original, either. The idea of sneaking vegetables into kids' food is a time-honored parenting trick, and Lapine's book was not the first: The largely unsung book Sneaky Veggies by Chris Fisk, for example, came out in August of 2006.
Spend 10 minutes comparing the Seinfeld and Lapine books, and you won't be able to seriously contend that there is plagiarism. (And in all the articles I've found about this tempest in a teapot, not one has pointed to a specific example of plagiarism.) Sure, the two books are based on the same unremarkable, unoriginal idea. And a handful of recipes employ some of the same obvious tricks (mostly based on hue, such as hiding sweet potato puree in a grilled cheese sandwich or spinach in brownies). But the books are quite different. For example, Seinfeld's recipe, titled "Mashed Potatoes," calls for simple cauliflower puree. Lapine's recipe for "Mystery Mashed Potatoes" specifies "White Puree," which is a separate recipe earlier in the book that consists of cauliflower, zucchini, and lemon juice. In a table comparing recipes, a New York Times blog notes that both books contain "Peanut Butter and Jelly Muffins" without noting that, among several other differences, Seinfeld calls for carrot puree while Lapine calls for "orange puree," based on sweet potatoes with the addition of carrots. Not that either trick is a revelation—fleshy vegetables like sweet potatoes and carrots have long been ingredients in cakes, pies, breads, and muffins.
Differences don't end at the recipes. The Lapine book is a straightforward cookbook. Seinfeld's is much more elaborate, from its unusual, hardcover-over-spiral binding (in the style of a family scrapbook), to its gorgeous line art and photography, to a writing style that captures the fantasy of Seinfeld as the reader's BFF. Every potentially similar recipe I've compared has had more than token differences—they seem to have been built independently, from the ground up, using different voices. Of those PB&J muffins, Lapine tells the story of Alison, who hates sweet potatoes but was fooled by the muffins: " 'Yum,' she squealed, 'these are great!' " Seinfeld says only, "I don't know who likes these more, kids or grown-ups."
Lapine, who has surely benefited from the publicity given to the Seinfeld book, seems particularly upset that Seinfeld got a spot on Oprah while she didn't. Oprah portraying an unoriginal idea as original does not constitute plagiarism by Seinfeld. But more to the point, there are reasons Seinfeld got on Oprah and Lapine didn't. They're surely the same reasons the publisher bought Seinfeld's book but not Lapine's: Jessica Seinfeld is gorgeous, charismatic, and married to an über-celebrity. Of course Oprah is going to put her on. Of course any publisher is going to buy whatever book she wants to produce. Of course Seinfeld's book is going to sell better than a book written by a normal person.
Plagiarism is a serious accusation. It can get students expelled; it can ruin writers' careers. And if it's occurred, it should. But the news media should take plagiarism seriously enough to not use the word unless it truly applies. Many things can be said of Seinfeld's book and its runaway success. A sad commentary on the state of parenting? I think so. A triumph of celebrity over substance? You bet. Further evidence of the decline of the West? Definitely. But an act of plagiarism? No way.