Maybe it's not best to ask online players if online properties are overvalued. But the general consensus, save for an occasional cautious voice, seems to be that the market is bullish, not bubbled. Rational, on the other hand, is an entirely different matter.

Insiders Say Market Is Bullish, Not Bubbly

When I was in Japan, I was told not to translate yen into dollars – it would only make me angry at the price of everything. Maybe that's the type of rationality we need here, as comparing company valuations and revenues will drive you batty.

Don't, for example, look at these numbers and balk:

Facebook, if moderately bubbly, is worth $15 billion, roughly half the value of Yahoo, with 32 times less revenue. If out-of-your-mind bubbly, Facebook is worth $100 billion, half the value of Google (and possibly a Google killer – if such a thing could exist), which is worth more than IBM, which pulls in eight times the revenue of Google.

And that makes MySpace, with a large nation's worth of membership and soon-to-be open platform, worth how much? More than $580 million, for sure…as much as Google?

It's hard to argue that Google isn't worth it – well, maybe not the $14 trillion suggested in some circles. Google is in position to bust more than a few lucrative blocks, encroaching on the turfs of the AT&Ts and Verizons of the world.

But a website with questionable revenue and no immediate plans to file an IPO, much less the ability to take over the known world like Google is doing?

Don't answer that. Too speculative.

The valuations, some say, are based more on low overhead and valuable audiences rather than revenue. Reaching those audiences, especially younger ones, at little cost, is what drives the inflation…er, not inflation…value.

"From an advertising perspective, brand budgets are increasing every year and new platforms are rapidly emerging to reach the young demographic that can't be reached through conventional channels," said Chris Redlitz, vice president of sales and marketing for Skyrider, a P2P monetization startup. 

"Blogs, social networks, mobile, gaming, video and peer to peer networks are new channels that reach the Gen Y demographic, and this is generating a significant amount of investment."

Redlitz joins a rather loud chorus of people saying this isn't 1999 all over again, that this time it's different. A critic is quick to note that this like when an addict denies his denial, or a teenager swears it's a love that lasts forever. Nevertheless, the players move ahead.

"I don't think this is a bubble," agrees Andy Beal, editor of Marketing Pilgrim. "In 1999, companies were throwing around money they didn't really have. Likewise, IPOs seemed to happen every day, with some wild valuations. This time around, there are solid companies making the deals, giving us a solid platform for continued increased value."

Both assessments are matched even by the mayor of Mountain View, Laura Macias, who presides over the heart of the madness where hundreds of tech startups have opened up shop just down the road from the Googleplex. On Tuesday, Macias confirmed that the climate is different this time around, saying there's "more substance to [these companies'] products."

And maybe so. Maybe 1999 really was the teenage romance that went kaput as soon as college began and the real world settled around us. Maybe (though it's hard not to doubt) this is the mature romance we learn to have later (shh, no cracks about the divorce rate, ok?).

The only thing that settles it is time – or a harsh morning sobriety – but until then, Silicon Valley parties on.