2006-13.
To be fair, my sample size on startup quality is about N = 15, so I'm sure I missed some good ones. And there are a lot of high-quality engineers (and people in general) in NYC. The engineers I met at Google NYC were a great crowd, for one example, and there are a lot of good people in finance.
I think NYC would be a great tech hub if the city could solve the cost-of-living problem, which would expand the pool of possible startups and help real technologists (as opposed to well-connected turds) get more play. Until then, the smart money's on places like Austin for the 2020s.