San Francisco has been a hot location for startups --- maybe the hot location, but at least prominent in the shortlist --- for over a decade. Where's the urgency coming from?
That's just not true. All tech companies have traditionally been down south. First San Jose, then Mountain View/Cupertino/Palo Alto. Few have traditionally been based in San Francisco proper.
The urgency is that this section of SF tax code was just discovered. The fear is that it will now be enforced, which would force the best SF-based companies to move.
I know that not to be true, unless there was a fallow period between the time that my company paid ridiculous $/sqft for space in SF to be among the VC-funded idiots of the time (2001) and today. But I don't buy that there was such a time. And, if anything, SF seems to have gotten even trendier since ~2005.
If you want to make the point that the particular wave of companies domiciled in SFBA are now anomalously likely to be going public, I won't argue with you, but that's a narrower point than the one I feel you originally made.
I was not around in 2001 so I will take your word on that one. It looks like there may have been a lull and then a resurgence around ~2007:
http://venturebeat.com/2007/01/14/weebly-offers-free-easy-we...
"The company is just three people from State College, PA. Co-founder David Rusenko originally told VentureBeat he would move to Mountain View. He changed his mind, he said, because he found a vibrant Internet start-up ecosystem in hipper San Francisco — the latest sign that San Francisco has become more of a magnet for these kinds of companies."
The urgency is that this section of SF tax code was just discovered. The fear is that it will now be enforced, which would force the best SF-based companies to move.