On Monday, Nobel-winning economist Paul Krugman said he expects the U.S. recession to end by September. The same day, the Organisation for Economic Co-operation and Development (OECD) published figures pointing to an economic "recovery" in its advanced member countries (which include the eurozone, the U.K., the U.S., and Japan). Great news! No wonder U.S. stocks erased an earlier decline on the day.

Not so fast
Stock traders should be more wary. Krugman's follow-up comments in a speech at the London School of Economics yesterday were much less buoyant. Suggesting that the damage from the U.S. recession could last "for a very long time," he raised the specter of a "global version of the Japanese 'lost decade.'" (On the heels of a real estate bubble and a banking crisis, Japan muddled through the 1990s with anemic growth.)

Krugman also said that the end of the recession "doesn't mean the same thing as it did in the old days"; unemployment could remain stubbornly higher than in previous recoveries, for example. That dovetails with comments made yesterday by another respected economist, Robert Shiller, according to which the "new normal" rate of GDP growth could be 2% or lower (compared to 3.1% average rate throughout the 1990s).

Winners and losers in a post-crisis economy
In other words, even if the so-called economic "green shoots" turn out to be genuine, it won't be business as usual now that households and businesses have to get by without resorting to massive leverage. That's a painful conclusion for companies that benefited from "masstige" ("mass" + "prestige") marketing, such as that of Saks (NYSE: SKS), Coach (NYSE: COH), Tiffany (NYSE: TIF), or Starbucks (Nasdaq: SBUX).

Still, not everyone loses in this new environment: With consumers adopting a new sense of parsimony, companies such as Target (NYSE: TGT), Wal-Mart (NYSE: WMT), and McDonald's (NYSE: MCD) are seizing the opportunity.

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