Ever wonder why a stock you own that reports "better-than-expected" earnings doesn't do anything on the news? Or worse, it goes down on the news?

Welcome to the new world of earnings surprises.

Indeed, it used to be the case that earnings surprises pushed stocks higher. A stock that beat earnings estimates was a stock with earnings momentum. Those were the stocks investors wanted to hold.

What has happened, however, is that companies were quick to catch on to the game. Nowadays, companies are skillful in talking down earnings estimates, making it easier to beat them. In effect, corporate America's mantra is to under promise and over deliver. And they have become well adept at it.

In such an environment, it is not surprising that earnings surprises have lost their luster as a driver of stock prices. Why? Because most analysts have two sets of earnings estimates for a company - the consensus estimate - the estimate that is around the estimates of all the other analysts following the company -- and the "real" estimate - the earnings the analyst truly believes the company will earn. What is happening is that companies are beating the lower consensus number but are not beating the higher "real" number. That's why the stocks that beat estimates sometimes don't rise.

What we have found to be a better indicator of a stock that is ready to run is when analysts actually revise upward a company's earnings estimates. Upward earnings revisions indicate the company actually beat the higher "real" earnings estimate number. And that's bullish.

How can you track a company's earnings revisions? Yahoo's finance site (http://quote.yahoo.com) provides earnings estimates and revision information on thousands of companies. Just click on the site and put in a stock symbol. Then click on the "research" button. You'll be taken to a page that shows analysts' earnings estimates over the last several days and months. Here, you can tell easily whether a company's earnings estimates are rising or falling.

Bottom line - Avoid companies with falling earnings estimates while focusing buying attention on those with rising estimates.