Shenzhen is a very different thing. It's important but not a challenger to SV. Huge startups come out of Beijing because it's the hub where the top students, founders, investors and regulators are.
If you look at Fortune's list of unicorns, 3 of the top 10 are in Beijing. As they build, they're strengthening the founder/techie/investor ecosystem in the city even further.
And yet Boston has some of the highest real estate prices in the country these days. (Fortunately you can commute out of it easier than in the Bay Area.) The Tech world doesn't begin and end with web/social/mobile.
I'd say the Research Universities, Medical Technology, Robotics, and Travel Technology that comes out of Boston is significantly ahead of Silicon Valley.
Automotive and related tech is quite small even with Tesla in the bay area. The number of automotive technology jobs is quite small. Automation technology from cars is picking up, but I doubt the number of jobs is very high in comparison to Detroit, Stuttgart, or Nagoya
There are a lot more aerospace outside of Silicon Valley with Aerobus and Boeing having little presence in California.
Google is #3 in cloud technology compared to Seattle/Redmond with AWS and Azure with significant marketshare advantage.
Amazon is 45% marketshare in US for online commerce. Logistics technology for them is mainly built in Seattle and Boston. Not much for Amazon going on in Silicon Valley. Alexa not made in Silicon Valley.
I'm still quite surprised people still believe Silicon Valley + SF lead in technology.
If you look at Fortune's list of unicorns, 3 of the top 10 are in Beijing. As they build, they're strengthening the founder/techie/investor ecosystem in the city even further.
http://fortune.com/unicorns/