Grab your "Dow 10,000" caps, Fools. The five-figure index is back.

You've probably heard by now: The Dow breached the 10K mark today, on the back of stellar earnings from Intel (NASDAQ:INTC) and JPMorgan Chase (NYSE:JPM). Traders screamed. Confetti fell. CNBC anchors giggled. I may have heard celebratory gunfire. While they may be materially irrelevant, these psychological barriers get investors riled up.

This milestone is exciting, of course. But who can forget watching the Dow fall below 10,000 almost exactly a year ago? The words "shock and awe" come to mind. What was then the sign of the world coming apart at the seams is today a sign that recovery has arrived.

As an example, I found this headline from last October:

Panicked global markets reel, Wall Street plunges below 10,000 pts

And then this one from this morning:

Dow 10000: Relief, Recovery on Trader Minds

The same level, one year apart, with polar opposite reactions. If that's not a sign of the powers of investor psychology, I don't know what is. 

More interestingly, it's been 10 years since the Dow first crossed the 10,000 mark. Curious about what the financial world looked like back then, I dug up a few broad metrics for comparison:

Metric

1999

Today

GDP

$9.4 trillion

$14.4 trillion*

Unemployment

4.2%

9.8%

Fed Funds Rate

4.75%

Zilch

U.S. Population

274 million

305 million

S&P 500 Earnings

$51.68

$65.39*

Consumer Confidence

134.0

53.07

*For 2008.

Of course, plenty will point to Dow 10,000 as a surefire sign that markets are dangerously zooming ahead out of control -- a more than 50% gain since March!

This may be true, but it's being slightly unfair to the calendar. Year to date, the Dow is up about 15%. Seeing how far parts of the economy have come since January -- particularly vast improvements in credit markets -- that seems positively reasonable. The March lows were purely a function of fears that Citigroup (NYSE:C) and Bank of America (NYSE:BAC) were about to implode and be nationalized. When that possibility blew over, it took with it huge risks to the economy, making colossal gains a sure thing.

At any rate, we want to know what you think. With the Dow at 10,000, where do we go from here? Take a moment to weigh in in the Fool poll below, and share your thoughts in the comment section, if you feel so inclined.