In the past three years alone, as the Chron is reporting via a new report by CB Richard Ellis, tech companies have leased 40% more office space than in the entire five-year period we now call the dot-com boom.

The biggest difference, perhaps, between then and now is the fact that more tech-sector companies have caught on to the fact that their employees would much rather live and work in San Francisco, rather than commute to the Peninsula, which has resulted in more big companies and startups alike grabbing up office space in the city.

As the Chron notes, though, this could spell bad news, especially for the real estate market, should the tech sector tank like it has before.

"When you look at the job-growth figures, it's so dominantly tech that should it falter, it would have a big impact on the market," said Colin Yasukochi, director of research and analysis at CBRE and the principal author of [the office market study].

Whether we're in a bubble has become a boring semantic debate. But we do know that this boom will end, because all booms end.

The real questions are when will it happen - and how painful will it be when it does?

Office rents in SoMa have risen a whopping 87 percent since 2009, with a big chunk of the city's 15.5 million square feet of newly occupied office space being in that neighborhood. A lot of that square footage was from big deals by companies like Airbnb, Square, Twitter, Yelp, Zendesk and Zynga. (Here's a look at Yelp's brand new headquarters at the renovated 140 New Montgomery.) And just like during the dot-com boom (when, dear readers, this editor was employed by a company that shall remain nameless who signed a ten-year lease for two floors of lavish space overlooking the Bay at Fisherman's Wharf only to fold within 18 months of signing that lease), many companies are leasing more space than they need. And that might be a bad sign.

All booms end, indeed, but will the city weather this cycle with some more resilience than last time? Is the industry smarter and more profitable than it was back then, when everyone was dizzyingly high on the idea that the marvelous Internet was going solve every last one of the world's problems? Will this be a soft bust, like a fall from a single story onto a big bouncy trampoline, or will we all fall hard, like a big bag of rocks off that same roof onto pavement? The next year or so may hold some answers.

Until then, happy holidays! Enjoy those bonuses!