This morning, I read about the potential merger of General Motors and Chrysler. Then I read about the benign rivalry of two divas of the blog world, Arianna Huffington and Tina Brown. Two stories that have nothing to do with each other? You would think. But actually, they do. They point to a new reality of the business world: Competition isn’t what it used to be. Competition becomes coopetition. Rivals become friends—or “frenemies” at least.

The mayhem in the markets hastens the trend. Who could have fathomed a few months ago that GM and Chrysler would be discussing a possible merger, while begging the government to provide financial aid for such a deal? It’s about survival. And during these nail-biter weeks, the bank chiefs–John Mack at Morgan Stanley , Lloyd Blankfein at Goldman Sachs , Vikram Pandit at Citigroup –have phoned one another, talking mergers, and sat together with Treasury Secretary Hank Paulson to shore the global financial markets.

“Coopetition”– or cooperative competition–has long been a practice in Silicon Valley, where companies vie to put the other out of business in one area and partner in another to gain an edge over a greater threat. Yet we’re seeing more coopetition lately. Yahoo formed an advertising partnership with Google , to fend off Microsoft –a deal currently hung up by antitrust regulators. “Frenemies,” two parties that love and hate one another simultaneously, proliferate in the Internet, media and ad worlds. WPP CEO Martin Sorrell has used that term to describe Google, since his advertising and marketing-service firms both compete with and rely on Google for ad revenues.

What happened to extreme rivalries? I grew up at Fortune covering Coke and Pepsi, so I remember what killer competition looks like. Twelve years ago, Roberto Goizueta, the late CEO of Coca-Cola , and Roger Enrico, PepsiCo’s CEO, both told me that they had never met one another. In fact, they had not tasted each other’s drinks in more than a decade. Can you imagine CEOs behaving that way today? PepsiCo’s current CEO, Indra Nooyi, tastes the products of competitors, including Coke, weekly. Muhtar Kent, Coke’s chief, does the same as he travels the globe. Extreme rivalry is now irrelevant because there are no longer just two competitors. And it’s not just the cola wars anymore. The market is fragmented with big, mid-sized  and niche players across multiple categories.

As for those Internet divas, Huffington and Brown, well, their coopetition on their respective ventures, the Huffington Post and the Daily Beast, speaks to the nature of the blog world: There’s infinite room for players, and blog-building comes by linking and cross-promoting. “Sweetheart, we need to figure out how to get you more traffic,” Arianna has told me, seemingly unfazed that we are technically competitors. Such coopetition suggests another way the business world has changed: A decade ago, the so-called Queen Bee syndrome practically guaranteed that powerful women rarely helped other women get ahead. There was only so much room at the top back then.

Women, studies have shown, tend toward collaborative leadership styles. Do you think women have an edge in this new world of coopetition?