The biggest story emerging from the World Economic Forum's annual meeting, set to convene in Davos, Switzerland, tomorrow, isn't about the financial crisis, the environment, or the wars raging on multiple fronts across the globe. It's about who's not showing up.

Portfolio.com has learned that Morgan Stanley CEO John Mack and Google's Sergey Brin, whose company hosts a hot-ticket Davos party every year, are among those who were initially listed among participants but aren't attending. Also on the no-show list: Chevron CEO David O'Reilly, who co-chaired at Davos last year.

They join a growing list of high-profile executives who have decided to stay away from the confab, which has long been the most prestigious business event for A-list financial and corporate leaders.

In the past few years, bankers, private equity investors, and hedge-fund managers have been the stars of the meeting, enthralling lesser participants such as prime ministers and Hollywood celebrities. This year, many of them are staying away, including onetime hedge-fund wunderkind Ken Griffin of Citadel Investments, whose fund lost 47 percent in 2008.

The New York Times, Wall Street Journal, and Financial Times reported this morning on other high-profile no-shows, including Goldman Sachs CEO Lloyd Blankfein and Citigroup CEO Vikram Pandit. John Thain, the recently deposed Merrill Lynch CEO, had already backed out, as had Richard Fuld, former CEO of Lehman Brothers. Sony CEO Sir Howard Stringer also sent his regrets.

Certainly, a case can be made for staying home to take care of business in a time of crisis. Perhaps just as important is the PR perception: Many of these executives headed to Davos on corporate jets—a now-unfortunate photo-op that in itself has become an embarrassment and cause of shareholder outrage that few can afford to weather.

A World Economic Forum spokesman says cancellations are "running more or less as last year," and that attendance is up slightly from last year, to just over 2,500. The Forum expects 40 world leaders this year, a record—and a clear sign of the shift of economic power away from the free markets and toward governments around the globe.

At least one banker is not only showing up but throwing a party to celebrate: Jamie Dimon, CEO of J.P. Morgan Chase.

One of the few bankers standing with his reputation intact, Dimon will host a cocktail party at the Tonic Piano Bar at the Hotel Europe on Thursday. No doubt those who are showing up at Davos to discuss the agenda—"Shaping the Post-Crisis World"—could use a drink.