The Dow Jones Industrial Average closed above 10,000 Wednesday, crossing a Rubicon whose ability to capture headlines is matched only by its statistical irrelevance.

Sure, the Dow s close at 10,015 is great, but at best, it will heighten investor conviction that the economic recovery has substance. At worst, it will prompt excessive optimism that could spur excessive buying at a high.

So which message is more important: Hooray, Dow 10,000, or Dow 10,000, so what?

"It's both," says Karl Mills, president and chief investment officer for Jurika Mills & Keifer in Oakland, Calif. "Psychologically, these numbers do have some meaning, in that they influence sentiment and will drive cash flows in and out of the market. As a basis for making a sustainable investment thesis, it's not that meaningful or predictive."

Against the backdrop of the calendar, the Dow s move is both heartening the index of 30 stocks last closed above 10,000 on Oct. 3, 2008, on its way down to a 12-month intraday low of 6,440 on March 9 and discouraging the Dow first hit 10,000 on March 29, 1999, and remains well below its peak of 14,198, reached Oct. 9, 2007.

Tommy Williams, president of Williams Financial Advisors in Shreveport, La., says small investors ought to avoid making investment moves based solely on headlines. There's a lot going on in terms of an economic recovery, but that doesn t mean growth and prosperity are back at full throttle.

"There are some favorable earnings reports and some encouraging economic fundamental numbers for retail sales, consumer sentiment, and if you go back and compare them to where we were six or eight months ago, they've been much more favorable than anybody would have thought," he says. "But right now we're in a period where emotions are driving the market much more so that economic fundamentals, and there are enough positive numbers out there to keep from thwarting that enthusiasm."

Like, say, the Dow topping 10,000.

"It might help investors get to the belief that the recovery is real," says Frank Ingarra, a co-portfolio manager at Hennessy Funds. "We might have a little pullback and some disappointment in the short term, but there are great opportunities."

Even the technical analysts, chart watchers like Richard Ross at Auerbach Grayson, see momentum blowing past the recent averages for key stock indexes. Using a standard technical analysis method called a Fibonacci retracement, he believes the index could go as high as 10,400 by the end of the year.

"You can't discount the psychological power of these targets, because history has shown they do have a kind of pull, but this is where we were 10 years ago, so let's not get too excited," he says. "A decade ago, we were celebrating the fall of every round number like it was a Super Bowl victory, like a sport. That gave rise to a bubble mentality. I'd like to see us avoid the euphoria and mania this time around. I'd rather see the unemployment rate go down than celebrate these big headlines figures. That would be a lot better for the economy."

There's also the question of what the index means to investors. While the Dow is narrow, and it's not weighted, meaning price changes to any of its components can affect the average, unlike the broader S&P 500, which is market weighted, giving price changes to the largest companies more impact.

"We actually think the S&P at 1100 is more meaningful," Mills says.

But Williams says investors can't draw conclusions from stock index numbers and must adjust to "the new normal," where economic fundamentals and market values are less reliant on boom-and-bust dynamics.

"What I'd say is enjoy the ride right now," he says. "But you better have a sell discipline if you're anywhere the stock market. The old buy, hold and hope strategy, I think, is dead."

Still, up is better than down. As Mills points out, the Dow at 10,000 represents a 53% gain since early March, "and that's a lot better than the alternative."