MENLO PARK, CALIF. (CNN/Money) - There is more enthusiasm in Silicon Valley today than at any moment in the last three years. If only that were reason enough to load up on tech stocks in 2004.

The optimism, buzz, excitement – you name it – are real. In the media and at the power-breakfast table, evidence of an honest-to-goodness recovery abound. Consider:

• The current issue of Business Week carries an almost-too-good-to-be-true assessment of how Cisco Systems today is stronger than ever, including before the bottom fell out of its markets in 2001. I was taken aback by the often-cautious magazine's unbridled bullishness, essentially arguing that Cisco is poised for new greatness. Right or wrong, this article will pump up a group of investors who are more than willing to be pumped up about Cisco's prospects.
• The Wall Street Journal on Tuesday ran a savvy piece explaining how Intel has re-tooled itself to be able to make chips that focus on mobility and smaller devices. It's a sign that no matter your opinion of the trajectory of the PC industry, Intel has made shrewd moves to ensure its survival.

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• The New York Times used the "r" word Wednesday in an article that addresses how even with a tech-market recovery, it's still tough to get a job here.

A partner in a major law firm I know told me that work from venture-backed startup companies is flowing in and that he can't find enough junior-level lawyers to staff the deals. This is the kind of comment you heard repeatedly in the bubble era.

Proof to me is the party index: A relatively prominent technology company that confined its holiday party last year to the employee cafeteria is holding a proper event this year. That happens when the market is on an upswing, not a downturn. I'll bet this particular company isn't the only one.

So why, if things are undeniably so good, would I argue that it's not necessarily time to back up the truck on tech stocks? A caveat to start with. I'm the guy who totally missed the move in Intel's shares from $15 to $32, as more than a few readers have been kind enough to point out to me.

But there's strong evidence to suggest that the market already has priced in the gains that only now are becoming apparent.

Take Cisco. Read the Business Week story carefully and you're reminded that Cisco's revenues are growing at about a 5 percent annual pace. A company given up for dead by investors can double its valuation. A company that's recognized as having survived but is growing in the single digits doesn't make for huge upside.

There's also the gnawing reality that technology is mature. Corporate spending still hasn't returned. When it does, it won't be with the wild-eyed enthusiasm of the mid- to late-1990s.

An analyst I know at a well-performing tech mutual fund told me recently he's amazed that investors in his fund aren't rebalancing their stakes, in other words, selling some of their winnings and investing them elsewhere.

Instead, they're letting too much ride on his fund, just as they did before the fall. Who says history never repeats itself?

It's truly a good sign when mergers run into turmoil because a third party wants to pay more. Witness the bizarre turn of events at Canadian software company Pivotal, which had agreed to sell itself to Oak Investment Partners.

Out of the blue, two different companies -- Onyx Software in Bellevue, Wash., and CDC Software of Hong Kong -- made bigger offers to buy Pivotal, which is spurning both companies. This sort of thing didn't happen between 2000 and the middle of this year.

Adam Lashinsky is a senior writer for Fortune magazine. Send e-mail to Adam at lashinskysbottomline@yahoo.com.

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