Is Silicon Valley still top for tech?

Rory Cellan-Jones asks whether California is still the best home for tech startups. He speaks to a video games executive, a venture capitalist, a gig-economy driver, a social entrepreneur, and the Dean of Stanford University’s Medical School to get their view. And Rachael Myrow, senior tech editor from Californian radio station KQED gives her take on whether Silicon Valley is still on top.