For awhile Monday it seemed as if it wasn't Columbus Day, 2006, but Columbus Day, 1999. You remember that autumn, when dot-com debutantes went public in Initial Public Offerings that valued mere start-ups in the tens of billions of dollars. A good idea, a few employees and a convincing investment banker was all that was needed to turn a pipe dream into the hot "stock du jour."

We all know how that rampant speculation ended. And given the exuberance of the millennium markets, Google's acquisition of YouTube late Monday for $1.6 billion seems downright conservative.

But with the Dow Jones Industrial Average at record highs, even in the face of North Korea's nuclear defiance, a worsening situation in Iraq, and a softening housing market — it's a fair bet to say that a degree of froth has returned to the corner of Broad and Wall Streets.

Not only does the Google deal demonstrate the long-awaited return of dot-com optimism, it also signals just how quickly companies in this space mature. Google, born in the post-bubble haze, is now a grown-up company in its own right — and its ardor in pursuing YouTube shows that it too can no longer grow just organically.

What sets this deal apart is that, for the first time in its short history, Google is paying for eyeballs — more than 30 million (that's in pairs, one assumes) a month. It is Google's biggest acquition ever, a fact that underscores the importance its founders put not only on video, but on the "community" that the sharing features of YouTube make possible.

Google believes that so-called "social networks" are the future of the Internet and with this deal has put its money behind the concept. In that vein, it also recently outbid Yahoo and Microsoft for the opportunity to be the exclusive search engine for NewsCorp's wildly popular MySpace.com.

In fact, video is the fastest-growing segment on the Internet. Now, teamed with Google, the future for YouTube seems infinite. Could a GoogleTV be the network of the future? Google is staking its money and reputation on it. Time will tell.